Wael Hozzein - Academia.edu (original) (raw)

Papers by Wael Hozzein

Phylogenetic tree showing the relationship of J. gansuensis YIM 002T with some other actinobacter... more Phylogenetic tree showing the relationship of J. gansuensis YIM 002T with some other actinobacteria based on 16S rRNA sequences. The maximum-likelihood tree was built using MEGA 5 [39]. Bootstrap values (percentages of 1000 replicates) are shown at branch points. Haloglycomyces albus was used as outgroup. (PDF 92 kb)

Number of gene clusters associated with antiSMASH. (DOCX 73 kb)

Microorganisms

Next-generation approaches have enabled researchers to deeply study the plant microbiota and to r... more Next-generation approaches have enabled researchers to deeply study the plant microbiota and to reveal how microbiota associated with plant roots has key effects on plant nutrition, disease resistance, and plant development. Although early “omics” experiments focused mainly on the species composition of microbial communities, new “meta-omics” approaches such as meta-transcriptomics provide hints about the functions of the microbes when interacting with their plant host. Here, we used an RNA-seq dataset previously generated for tomato (Solanum lycopersicum) plants growing on different native soils to test the hypothesis that host-targeted transcriptomics can detect the taxonomic and functional diversity of root microbiota. Even though the sequencing throughput for the microbial populations was limited, we were able to reconstruct the microbial communities and obtain an overview of their functional diversity. Comparisons of the host transcriptome and the meta-transcriptome suggested t...

International Journal of Systematic and Evolutionary Microbiology

Two novel strains, designated SYSU L10167T and SYSU L10180T, were isolated from sediment sampled ... more Two novel strains, designated SYSU L10167T and SYSU L10180T, were isolated from sediment sampled at Dabancheng saline lake in Xinjiang, PR China. A polyphasic approach was used to clarify the taxonomic positions of the two strains. Cells of the isolates were curved ring-like, horseshoe-shaped or rod-shaped, non-motile and non-spore-forming. Cells were Gram-stain-negative, aerobic, heterotrophic and rose-pigmented. The phylogenetic trees based on 16S rRNA gene sequences showed that strains SYSU L10167T and SYSU L10180T formed a distinct lineage within the genus Cyclobacterium . Strains SYSU L10167T and SYSU L10180T showed highest similarities to Cyclobacterium jeungdonense KCTC 23150T (98.0 and 97.4%, respectively). Results of genomic analyses (including average nucleotide identity, digital DNA–DNA hybridization and the marker gene tree) and pan-genome analysis further confirmed that strains SYSU L10167T and SYSU L10180T were separate from each other and other species of the genus Cy...

Marine Life Science & Technology

Microplastics are a highly concerning pollutant that have gained attention from the scientific co... more Microplastics are a highly concerning pollutant that have gained attention from the scientific community and other regulatory authorities due to their potential risks to organisms and ecosystems. Microplastics are widespread in both terrestrial and aquatic ecosystems and can be found even in Antarctica and deep-sea sediments. The ability to survive for long periods in the environment and their aptitude of inter-and intra-environmental translocation can prompt poor environmental outcomes. The adsorption of heavy metals and other toxic persistent organic pollutants is a further cause for concern. Furthermore, microplastics enable the development of a distinct microbial niche within an ecosystem, which could potentially impair ecosystem function by promoting the growth of selective microbial communities. The acquisition of metal-resistant, antibiotic-resistant genes, and the enrichment of antibiotic-resistant bacteria on microplastic surfaces have recently been reported. Moreover, some studies have also reported the colonization of pathogenic bacterial strains such as Vibrio spp. on microplastic surfaces. This review aims to address the sources of microplastic pollution in the freshwater and marine environments and to discuss their potential functions in the environment.

Biomolecules

The use of actinomycetes for improving soil fertility and plant production is an attractive strat... more The use of actinomycetes for improving soil fertility and plant production is an attractive strategy for developing sustainable agricultural systems due to their effectiveness, eco-friendliness, and low production cost. Out of 17 species isolated from the soil rhizosphere of legume crops, 4 bioactive isolates were selected and their impact on 5 legumes: soybean, kidney bean, chickpea, lentil, and pea were evaluated. According to the morphological and molecular identification, these isolates belong to the genus Streptomyces. Here, we showed that these isolates increased soil nutrients and organic matter content and improved soil microbial populations. At the plant level, soil enrichment with actinomycetes increased photosynthetic reactions and eventually increased legume yield. Actinomycetes also increased nitrogen availability in soil and legume tissue and seeds, which induced the activity of key nitrogen metabolizing enzymes, e.g., glutamine synthetase, glutamate synthase, and nitr...

Antibiotics

In the present study, we investigated the actinomycetes associated with the Red Sea-derived soft ... more In the present study, we investigated the actinomycetes associated with the Red Sea-derived soft coral Sarcophyton glaucum in terms of biological and chemical diversity. Three strains were cultivated and identified to be members of genera Micromonospora, Streptomyces, and Nocardiopsis; out of them, Micromonospora sp. UR17 was putatively characterized as a new species. In order to explore the chemical diversity of these actinobacteria as far as possible, they were subjected to a series of fermentation experiments under altering conditions, that is, solid and liquid fermentation along with co-fermentation with a mycolic acid-containing strain, namely Nocardia sp. UR23. Each treatment was found to affect these actinomycetes differently in terms of biological activity (i.e., antitrypanosomal activity) and chemical profiles evidenced by LC-HRES-MS-based metabolomics and multivariate analysis. Thereafter, orthogonal projections to latent structures discriminant analysis (OPLS-DA) suggeste...

Extremophilic Microbes and Metabolites - Diversity, Bioprespecting and Biotechnological Applications [Working Title]

Screening for microbial secondary metabolites (SMs) has attracted the attention of the scientific... more Screening for microbial secondary metabolites (SMs) has attracted the attention of the scientific community since 1940s. In fact, since the discovery of penicillin, intensive researches have been conducted worldwide in order to detect and identify novel microbial secondary metabolites. As a result, the discovery of novel SMs has been decreased significantly by using traditional experiments. Therefore, searching for new techniques to discover novel SMs was one of the most priority objectives. However, the development and advances of omics-based techniques such as metabolomics and genomics have revealed the potential of discovering novel SMs which were coded in the microorganisms' DNA but not expressed in the lab media or might be produced in undetectable amount by detecting the biosynthesis gene clusters (BGCs) that are associated with the biosynthesis of secondary metabolites. Nowadays, the development and integration of gene editing tools such as CRISPR-Cas9 in metabolomics provide a successful platform for the identification and detection of known and novel SMs and also to increase the production of SMs.

Toxins

Calf diarrhea is one of the considerable infectious diseases in calves, which results in tremendo... more Calf diarrhea is one of the considerable infectious diseases in calves, which results in tremendous economic losses globally. To determine the prevalence of Shiga-toxigenic E. coli (STEC) and Enterotoxigenic E. coli (ETEC) incriminated in calf diarrhea, with special reference to Shiga- toxins genes (stx1 and stx2) and enterotoxins genes (lt and sta) that govern their pathogenesis, as well as the virulence genes; eaeA (intimin) and f41(fimbrial adhesion), and the screening of their antibiogram and antimicrobial resistance genes; aadB, sul1, and bla-TEM, a total of 274 fecal samples were collected (April 2018–Feb 2019) from diarrheic calves at different farms in El-Sharqia Governorate, Egypt. The bacteriological examination revealed that the prevalence of E. coli in diarrheic calves was 28.8%. The serotyping of the isolated E. coli revealed 7 serogroups; O26, O128, O111, O125, O45, O119 and O91. Furthermore, the Congo red binding test was carried out, where 89.8% of the examined strai...

Microorganisms

The diversity of actinomycetes associated with the marine sponge Coscinoderma mathewsi collected ... more The diversity of actinomycetes associated with the marine sponge Coscinoderma mathewsi collected from Hurghada (Egypt) was studied. Twenty-three actinomycetes were separated and identified based on the 16S rDNA gene sequence analysis. Out of them, three isolates were classified as novel species of the genera Micromonospora, Nocardia, and Gordonia. Genome sequencing of actinomycete strains has revealed many silent biosynthetic gene clusters and has shown their exceptional capacity for the production of secondary metabolites, not observed under classical cultivation conditions. Therefore, the effect of mycolic-acid-containing bacteria or mycolic acid on the biosynthesis of cryptic natural products was investigated. Sponge-derived actinomycete Micromonospora sp. UA17 was co-cultured using liquid fermentation with two mycolic acid-containing actinomycetes (Gordonia sp. UA19 and Nocardia sp. UA 23), or supplemented with pure mycolic acid. LC-HRESIMS data were analyzed to compare natural ...

Current Microbiology

A Gram stain-positive, rod-shaped and motile bacterium, designated SYSU G01003T was isolated from... more A Gram stain-positive, rod-shaped and motile bacterium, designated SYSU G01003T was isolated from a sediment sample collected from tepid spring in Tengchong, Yunnan province, southwestern China. Growth observed at temperature ranging 28–37 °C (optimum 37 °C) and pH 6.0–8.0 (optimum pH 7.0). Tolerance to NaCl was up to 2.5% (w/v) (optimal in the absence of NaCl). The cell wall peptidoglycan is meso-2,6-diaminopimelic acid and MK-7 as the only respiratory quinone. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and unidentified aminophospholipid, phospholipid, and polar lipid. The major fatty acids are C16:0, anteiso-C15:0 and C14:0. The genomic DNA G + C content of the type strain was 54.0 mol%. The average nucleotide identity (ANIb and ANIm) values between SYSU G01003T and Paenibacillus azotifigens LMG 29963T were below the cut-off level (95–96%) recommended as the average nucleotide identity (ANI) criterion for interspecies identity. Based on the above results strain SYSU G01003T represents a novel species of the genus Paenibacillus, for which the name Paenibacillus yunnanensis sp. nov. is proposed. The type strain, SYSU G01003T (=KCTC 43132T = CGMCC 1.17384T).

Materials

New generations of hyperbranched aramids were synthesized from diarylamine and methyl acrylate us... more New generations of hyperbranched aramids were synthesized from diarylamine and methyl acrylate using an AB2 monomer approach in a straightforward one-pot preparation. The chemical structure of hyperbranched Phenylenediamine/Methyl Acrylate HB(PDMA was confirmed by Fourier Transform Infrared (FTIR) and Nuclear Magnetic Resonance (1HNMR) spectroscopy. In addition, the particle’s size and distribution were recorded using Dynamic Light Scattering (DLS). Moreover, the synthesized HB(PDMA)s displayed broad-spectrum antimicrobial activities against Gram-positive and Gram-negative bacteria as well as yeast strains and anti-biofilm activity where the highest activity was attributed to HB(PDMA)G4 at the lowest Minimum Inhibitory, Minimum Bactericidal, and Fungicidal Concentrations (MIC, MBC, and MFC, respectively). Furthermore, the HB(PDMA)s expressed anti-bacterial activity against isolated Pseudomonas sp. (R301) at a salinity of 35,000 ppm (NaCl). In addition, they revealed different corros...

Molecules

The Egyptian petroleum industries are incurring severe problems with corrosion, particularly corr... more The Egyptian petroleum industries are incurring severe problems with corrosion, particularly corrosion that is induced by sulfidogenic microbial activities in harsh salinity environments despite extensively using biocides and metal corrosion inhibitors. Therefore, in this study, a synthesized cationic gemini surfactant (SCGS) was tested as a broad-spectrum antimicrobial, anti-bacterial, anti-candida, anti-fungal, anti-biofilm (anti-adhesive), and bio-dispersion agent. The SCGS was evaluated as a biocide against environmental sulfidogenic-bacteria and as a corrosion inhibitor for a high salinity cultivated medium. The SCGS displayed wide spectrum antimicrobial activity with minimum bactericidal/fungicidal inhibitory concentrations. The SCGS demonstrated anti-bacterial, anti-biofilm, and bio-dispersion activity. The SCGS exhibited bactericidal activity against environmental sulfidogenic bacteria and the highest corrosion inhibition efficiency of 93.8% at 5 mM. Additionally, the SCGS d...

Nature Communications

Several recent studies have shown the presence of genes for the key enzyme associated with archae... more Several recent studies have shown the presence of genes for the key enzyme associated with archaeal methane/alkane metabolism, methyl-coenzyme M reductase (Mcr), in metagenome-assembled genomes (MAGs) divergent to existing archaeal lineages. Here, we study the mcr-containing archaeal MAGs from several hot springs, which reveal further expansion in the diversity of archaeal organisms performing methane/alkane metabolism. Significantly, an MAG basal to organisms from the phylum Thaumarchaeota that contains mcr genes, but not those for ammonia oxidation or aerobic metabolism, is identified. Together, our phylogenetic analyses and ancestral state reconstructions suggest a mostly vertical evolution of mcrABG genes among methanogens and methanotrophs, along with frequent horizontal gene transfer of mcr genes between alkanotrophs. Analysis of all mcr-containing archaeal MAGs/genomes suggests a hydrothermal origin for these microorganisms based on optimal growth temperature predictions. The...

Environmental Science and Pollution Research

Actinomycetes are a group of the Gram-positive bacteria famous for their antimicrobial, anticance... more Actinomycetes are a group of the Gram-positive bacteria famous for their antimicrobial, anticancer, anti-parasitic, and anti-inflammatory activities. This study aimed to investigate the efficacy of two bacterial extracts derived from two soil actinomycete strains (S19 and G30) against carbon tetrachloride (CCl4)–induced nephrotoxicity in experimental rats. Sixty-four male rats were assigned to four groups of 16 rats in each group. The 1st group was kept as a normal (control) group and given corn oil combined with the used production medium, while the 2nd group received only CCl4 (CCl4 group). On the other hand, the 3rd group (CCl4+S19) was administered CCl4 and the extract of the actinomycete strain S19 and the 4th group (CCl4+G30) received CCl4 and the extract of the actinomycete strain G30, both treatments for 8 weeks. The results revealed that the two actinomycete extracts S19 and G30 could significantly (p < 0.01) lower the elevated levels of serum creatinine, urea, and uric acid caused by the CCl4 administration. Additionally, the two actinomycete extracts improved the decreased serum total protein. Interestingly, treatment of the CCl4-intoxicated rats with S19 and G30 extracts remarkably reversed the lowered renal glutathione (GSH), glutathione peroxidase (GSH-Px), peroxidase (Px) and superoxide dismutase (SOD) activities, and the elevated lipid peroxidation (LPO) levels. The histopathological examination of the treated kidney revealed that the two actinomycete extracts improved rats against CCl4-induced kidney lesions. The present results suggested that the protective effect of the two actinomycete extracts may rely on its effect on reducing the oxidative stress and improving the antioxidant defense system.

International Journal of Systematic and Evolutionary Microbiology

A Gram-stain-negative, aerobic, rod-shaped bacterium, designated strain C8-1, was isolated from t... more A Gram-stain-negative, aerobic, rod-shaped bacterium, designated strain C8-1, was isolated from the rhizosphere soil of Nicotiana tabacum L. collected from Kunming, south-west China. The cells showed oxidase-positive and catalase-positive reactions. Growth was observed at 10-40 °C, at pH 6.0-8.0 and in the presence of up to 1 % (w/v) NaCl, with optimal growth at 30 °C and pH 7.0. The predominant isoprenoid quinone was Q-8. The major fatty acids were identified as iso-C15 : 0, iso-C17 : 0 and iso-C17 : 1ω9c. The cellular polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine, five unidentified phospholipids and two unidentified aminophospholipids. The genomic DNA G+C content was 70.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain C8-1 should be assigned to the genus Lysobacter. 16S rRNA gene sequence similarity analysis showed that strain C8-1 was closely related to Lysobacter cavernae YIM C01544 (98.6 %), Lysobacter soli DCY21 (97.6 %), Lysobacter panacisoli CJ29 (97.3 %), Lysobacter firmicutimachus PB-6250 (97.3 %), Lysobacter niastensis GH41-7 (97.3 %) and Lysobacter gummosus KCTC 12132 (97.1 %). DNA-DNA hybridization data indicated that the isolate may represent a novel genomic species belonging to the genus Lysobacter. Polyphasic taxonomic characteristics indicated that strain C8-1 represents a novel species of the genus Lysobacter, for which the name Lysobacter tabacisoli sp. nov. is proposed. The type strain is C8-1 (=KCTC 62034=CGMCC 1.16271) .

Archives of Microbiology

A Gram-positive and aerobic actinobacterium, strain SYSU D8006, was isolated from a desert sand s... more A Gram-positive and aerobic actinobacterium, strain SYSU D8006, was isolated from a desert sand sample collected from Gurbantunggut desert, China. Phenotypically, the strain was found to grow at 14-50 °C, pH 6.0-9.0 and in the presence of up to 4% (w/v) NaCl. The chemotaxonomic features of strain SYSU D8006 included menaquinone MK-9(H) as the respiratory quinone, diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannoside as known polar lipids, iso-C iso-C C ω8c and C ω9c as the predominant fatty acids, and arabinose, galactose and glucose as the whole cell sugars. Strain SYSU D8006 shared the highest 16S rRNA gene sequence identity with Blastococcus jejuensis DSM 19597 (98.2%). Based on the analyses of the phenotypic, genotypic and phylogenetic characteristics, strain SYSU D8006 is characterized to represent a novel species of the genus Blastococcus, for which the name Blastococcus deserti sp. nov. is proposed. The type strain is SYSU D8006 (= CGMCC 1.15935 = KCTC 49026 = CPCC 204618).

International journal of systematic and evolutionary microbiology, 2018

A novel strain, designated Y1A-10 4-9-1, with Gram-stain-positive and rod-shaped cells, was isola... more A novel strain, designated Y1A-10 4-9-1, with Gram-stain-positive and rod-shaped cells, was isolated from paddy soil in Yingtan, Jiangxi, China. Cells were 0.15-0.2 µm wide and 1.5-3.3 µm long. The optimal growth temperature was 30 °C and the optimal pH was 7.0. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the novel strain is closely related to Propionicimonas paludicola JCM 11933 (98.57 %). The genomic DNA G+C content was 63.9 mol%. The predominant menaquinone was MK-9(H4) and meso-diaminopimelic acid was present in the cell-wall peptidoglycan layer. The major polar lipids were diphosphatidylglycerol, one unidentified phospholipid and two unidentified lipids. The dominant cellular fatty acids detected were anteiso-C15 : 0 and iso-C16 : 0. The phylogenetic and phenotypic results supported that strain Y1A-10 4-9-1 is a novel species of the genus Propionicimonas, for which the name Propionicimonas ferrireducens sp. nov. is proposed. The type strain is Y1A-10 4...

Antonie van Leeuwenhoek, Jan 17, 2018

A gene encoding a β-xylosidase (designated as Thxyl43A) was cloned from strain Thermobifida halot... more A gene encoding a β-xylosidase (designated as Thxyl43A) was cloned from strain Thermobifida halotolerans YIM 90462. The open reading frame of this gene encodes 550 amino acid residues. The gene was over-expressed in Escherichia coli and the recombinant protein was purified. The monomeric Thxyl43A protein presented a molecular mass of 61.5 kDa. When p-nitrophenyl-β-d-xylopyranoside was used as the substrate, recombinant Thxyl43A exhibited optimal activity at 55 °C and pH 4.0 to 7.0, being thermostable by maintaining 47% of its activity after 30 h incubation at 55 °C. The recombinant enzyme retained more than 80% residual activity after incubation at pH range of 4.0 to 12.0 for 24 h, respectively, which indicated notable thermostability and pH stability of Thxyl43A. Moreover, Thxyl43A displayed high catalytic activity (> 60%) in presence of 5-35% NaCl (w/v) or 1-20% ionic liquid (w/v) or 1-50 mM xylose. These properties suggest that Thxyl43A has potential for promoting hemicellulos...

Phylogenetic tree showing the relationship of J. gansuensis YIM 002T with some other actinobacter... more Phylogenetic tree showing the relationship of J. gansuensis YIM 002T with some other actinobacteria based on 16S rRNA sequences. The maximum-likelihood tree was built using MEGA 5 [39]. Bootstrap values (percentages of 1000 replicates) are shown at branch points. Haloglycomyces albus was used as outgroup. (PDF 92 kb)

Number of gene clusters associated with antiSMASH. (DOCX 73 kb)

Microorganisms

Next-generation approaches have enabled researchers to deeply study the plant microbiota and to r... more Next-generation approaches have enabled researchers to deeply study the plant microbiota and to reveal how microbiota associated with plant roots has key effects on plant nutrition, disease resistance, and plant development. Although early “omics” experiments focused mainly on the species composition of microbial communities, new “meta-omics” approaches such as meta-transcriptomics provide hints about the functions of the microbes when interacting with their plant host. Here, we used an RNA-seq dataset previously generated for tomato (Solanum lycopersicum) plants growing on different native soils to test the hypothesis that host-targeted transcriptomics can detect the taxonomic and functional diversity of root microbiota. Even though the sequencing throughput for the microbial populations was limited, we were able to reconstruct the microbial communities and obtain an overview of their functional diversity. Comparisons of the host transcriptome and the meta-transcriptome suggested t...

International Journal of Systematic and Evolutionary Microbiology

Two novel strains, designated SYSU L10167T and SYSU L10180T, were isolated from sediment sampled ... more Two novel strains, designated SYSU L10167T and SYSU L10180T, were isolated from sediment sampled at Dabancheng saline lake in Xinjiang, PR China. A polyphasic approach was used to clarify the taxonomic positions of the two strains. Cells of the isolates were curved ring-like, horseshoe-shaped or rod-shaped, non-motile and non-spore-forming. Cells were Gram-stain-negative, aerobic, heterotrophic and rose-pigmented. The phylogenetic trees based on 16S rRNA gene sequences showed that strains SYSU L10167T and SYSU L10180T formed a distinct lineage within the genus Cyclobacterium . Strains SYSU L10167T and SYSU L10180T showed highest similarities to Cyclobacterium jeungdonense KCTC 23150T (98.0 and 97.4%, respectively). Results of genomic analyses (including average nucleotide identity, digital DNA–DNA hybridization and the marker gene tree) and pan-genome analysis further confirmed that strains SYSU L10167T and SYSU L10180T were separate from each other and other species of the genus Cy...

Marine Life Science & Technology

Microplastics are a highly concerning pollutant that have gained attention from the scientific co... more Microplastics are a highly concerning pollutant that have gained attention from the scientific community and other regulatory authorities due to their potential risks to organisms and ecosystems. Microplastics are widespread in both terrestrial and aquatic ecosystems and can be found even in Antarctica and deep-sea sediments. The ability to survive for long periods in the environment and their aptitude of inter-and intra-environmental translocation can prompt poor environmental outcomes. The adsorption of heavy metals and other toxic persistent organic pollutants is a further cause for concern. Furthermore, microplastics enable the development of a distinct microbial niche within an ecosystem, which could potentially impair ecosystem function by promoting the growth of selective microbial communities. The acquisition of metal-resistant, antibiotic-resistant genes, and the enrichment of antibiotic-resistant bacteria on microplastic surfaces have recently been reported. Moreover, some studies have also reported the colonization of pathogenic bacterial strains such as Vibrio spp. on microplastic surfaces. This review aims to address the sources of microplastic pollution in the freshwater and marine environments and to discuss their potential functions in the environment.

Biomolecules

The use of actinomycetes for improving soil fertility and plant production is an attractive strat... more The use of actinomycetes for improving soil fertility and plant production is an attractive strategy for developing sustainable agricultural systems due to their effectiveness, eco-friendliness, and low production cost. Out of 17 species isolated from the soil rhizosphere of legume crops, 4 bioactive isolates were selected and their impact on 5 legumes: soybean, kidney bean, chickpea, lentil, and pea were evaluated. According to the morphological and molecular identification, these isolates belong to the genus Streptomyces. Here, we showed that these isolates increased soil nutrients and organic matter content and improved soil microbial populations. At the plant level, soil enrichment with actinomycetes increased photosynthetic reactions and eventually increased legume yield. Actinomycetes also increased nitrogen availability in soil and legume tissue and seeds, which induced the activity of key nitrogen metabolizing enzymes, e.g., glutamine synthetase, glutamate synthase, and nitr...

Antibiotics

In the present study, we investigated the actinomycetes associated with the Red Sea-derived soft ... more In the present study, we investigated the actinomycetes associated with the Red Sea-derived soft coral Sarcophyton glaucum in terms of biological and chemical diversity. Three strains were cultivated and identified to be members of genera Micromonospora, Streptomyces, and Nocardiopsis; out of them, Micromonospora sp. UR17 was putatively characterized as a new species. In order to explore the chemical diversity of these actinobacteria as far as possible, they were subjected to a series of fermentation experiments under altering conditions, that is, solid and liquid fermentation along with co-fermentation with a mycolic acid-containing strain, namely Nocardia sp. UR23. Each treatment was found to affect these actinomycetes differently in terms of biological activity (i.e., antitrypanosomal activity) and chemical profiles evidenced by LC-HRES-MS-based metabolomics and multivariate analysis. Thereafter, orthogonal projections to latent structures discriminant analysis (OPLS-DA) suggeste...

Extremophilic Microbes and Metabolites - Diversity, Bioprespecting and Biotechnological Applications [Working Title]

Screening for microbial secondary metabolites (SMs) has attracted the attention of the scientific... more Screening for microbial secondary metabolites (SMs) has attracted the attention of the scientific community since 1940s. In fact, since the discovery of penicillin, intensive researches have been conducted worldwide in order to detect and identify novel microbial secondary metabolites. As a result, the discovery of novel SMs has been decreased significantly by using traditional experiments. Therefore, searching for new techniques to discover novel SMs was one of the most priority objectives. However, the development and advances of omics-based techniques such as metabolomics and genomics have revealed the potential of discovering novel SMs which were coded in the microorganisms' DNA but not expressed in the lab media or might be produced in undetectable amount by detecting the biosynthesis gene clusters (BGCs) that are associated with the biosynthesis of secondary metabolites. Nowadays, the development and integration of gene editing tools such as CRISPR-Cas9 in metabolomics provide a successful platform for the identification and detection of known and novel SMs and also to increase the production of SMs.

Toxins

Calf diarrhea is one of the considerable infectious diseases in calves, which results in tremendo... more Calf diarrhea is one of the considerable infectious diseases in calves, which results in tremendous economic losses globally. To determine the prevalence of Shiga-toxigenic E. coli (STEC) and Enterotoxigenic E. coli (ETEC) incriminated in calf diarrhea, with special reference to Shiga- toxins genes (stx1 and stx2) and enterotoxins genes (lt and sta) that govern their pathogenesis, as well as the virulence genes; eaeA (intimin) and f41(fimbrial adhesion), and the screening of their antibiogram and antimicrobial resistance genes; aadB, sul1, and bla-TEM, a total of 274 fecal samples were collected (April 2018–Feb 2019) from diarrheic calves at different farms in El-Sharqia Governorate, Egypt. The bacteriological examination revealed that the prevalence of E. coli in diarrheic calves was 28.8%. The serotyping of the isolated E. coli revealed 7 serogroups; O26, O128, O111, O125, O45, O119 and O91. Furthermore, the Congo red binding test was carried out, where 89.8% of the examined strai...

Microorganisms

The diversity of actinomycetes associated with the marine sponge Coscinoderma mathewsi collected ... more The diversity of actinomycetes associated with the marine sponge Coscinoderma mathewsi collected from Hurghada (Egypt) was studied. Twenty-three actinomycetes were separated and identified based on the 16S rDNA gene sequence analysis. Out of them, three isolates were classified as novel species of the genera Micromonospora, Nocardia, and Gordonia. Genome sequencing of actinomycete strains has revealed many silent biosynthetic gene clusters and has shown their exceptional capacity for the production of secondary metabolites, not observed under classical cultivation conditions. Therefore, the effect of mycolic-acid-containing bacteria or mycolic acid on the biosynthesis of cryptic natural products was investigated. Sponge-derived actinomycete Micromonospora sp. UA17 was co-cultured using liquid fermentation with two mycolic acid-containing actinomycetes (Gordonia sp. UA19 and Nocardia sp. UA 23), or supplemented with pure mycolic acid. LC-HRESIMS data were analyzed to compare natural ...

Current Microbiology

A Gram stain-positive, rod-shaped and motile bacterium, designated SYSU G01003T was isolated from... more A Gram stain-positive, rod-shaped and motile bacterium, designated SYSU G01003T was isolated from a sediment sample collected from tepid spring in Tengchong, Yunnan province, southwestern China. Growth observed at temperature ranging 28–37 °C (optimum 37 °C) and pH 6.0–8.0 (optimum pH 7.0). Tolerance to NaCl was up to 2.5% (w/v) (optimal in the absence of NaCl). The cell wall peptidoglycan is meso-2,6-diaminopimelic acid and MK-7 as the only respiratory quinone. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and unidentified aminophospholipid, phospholipid, and polar lipid. The major fatty acids are C16:0, anteiso-C15:0 and C14:0. The genomic DNA G + C content of the type strain was 54.0 mol%. The average nucleotide identity (ANIb and ANIm) values between SYSU G01003T and Paenibacillus azotifigens LMG 29963T were below the cut-off level (95–96%) recommended as the average nucleotide identity (ANI) criterion for interspecies identity. Based on the above results strain SYSU G01003T represents a novel species of the genus Paenibacillus, for which the name Paenibacillus yunnanensis sp. nov. is proposed. The type strain, SYSU G01003T (=KCTC 43132T = CGMCC 1.17384T).

Materials

New generations of hyperbranched aramids were synthesized from diarylamine and methyl acrylate us... more New generations of hyperbranched aramids were synthesized from diarylamine and methyl acrylate using an AB2 monomer approach in a straightforward one-pot preparation. The chemical structure of hyperbranched Phenylenediamine/Methyl Acrylate HB(PDMA was confirmed by Fourier Transform Infrared (FTIR) and Nuclear Magnetic Resonance (1HNMR) spectroscopy. In addition, the particle’s size and distribution were recorded using Dynamic Light Scattering (DLS). Moreover, the synthesized HB(PDMA)s displayed broad-spectrum antimicrobial activities against Gram-positive and Gram-negative bacteria as well as yeast strains and anti-biofilm activity where the highest activity was attributed to HB(PDMA)G4 at the lowest Minimum Inhibitory, Minimum Bactericidal, and Fungicidal Concentrations (MIC, MBC, and MFC, respectively). Furthermore, the HB(PDMA)s expressed anti-bacterial activity against isolated Pseudomonas sp. (R301) at a salinity of 35,000 ppm (NaCl). In addition, they revealed different corros...

Molecules

The Egyptian petroleum industries are incurring severe problems with corrosion, particularly corr... more The Egyptian petroleum industries are incurring severe problems with corrosion, particularly corrosion that is induced by sulfidogenic microbial activities in harsh salinity environments despite extensively using biocides and metal corrosion inhibitors. Therefore, in this study, a synthesized cationic gemini surfactant (SCGS) was tested as a broad-spectrum antimicrobial, anti-bacterial, anti-candida, anti-fungal, anti-biofilm (anti-adhesive), and bio-dispersion agent. The SCGS was evaluated as a biocide against environmental sulfidogenic-bacteria and as a corrosion inhibitor for a high salinity cultivated medium. The SCGS displayed wide spectrum antimicrobial activity with minimum bactericidal/fungicidal inhibitory concentrations. The SCGS demonstrated anti-bacterial, anti-biofilm, and bio-dispersion activity. The SCGS exhibited bactericidal activity against environmental sulfidogenic bacteria and the highest corrosion inhibition efficiency of 93.8% at 5 mM. Additionally, the SCGS d...

Nature Communications

Several recent studies have shown the presence of genes for the key enzyme associated with archae... more Several recent studies have shown the presence of genes for the key enzyme associated with archaeal methane/alkane metabolism, methyl-coenzyme M reductase (Mcr), in metagenome-assembled genomes (MAGs) divergent to existing archaeal lineages. Here, we study the mcr-containing archaeal MAGs from several hot springs, which reveal further expansion in the diversity of archaeal organisms performing methane/alkane metabolism. Significantly, an MAG basal to organisms from the phylum Thaumarchaeota that contains mcr genes, but not those for ammonia oxidation or aerobic metabolism, is identified. Together, our phylogenetic analyses and ancestral state reconstructions suggest a mostly vertical evolution of mcrABG genes among methanogens and methanotrophs, along with frequent horizontal gene transfer of mcr genes between alkanotrophs. Analysis of all mcr-containing archaeal MAGs/genomes suggests a hydrothermal origin for these microorganisms based on optimal growth temperature predictions. The...

Environmental Science and Pollution Research

Actinomycetes are a group of the Gram-positive bacteria famous for their antimicrobial, anticance... more Actinomycetes are a group of the Gram-positive bacteria famous for their antimicrobial, anticancer, anti-parasitic, and anti-inflammatory activities. This study aimed to investigate the efficacy of two bacterial extracts derived from two soil actinomycete strains (S19 and G30) against carbon tetrachloride (CCl4)–induced nephrotoxicity in experimental rats. Sixty-four male rats were assigned to four groups of 16 rats in each group. The 1st group was kept as a normal (control) group and given corn oil combined with the used production medium, while the 2nd group received only CCl4 (CCl4 group). On the other hand, the 3rd group (CCl4+S19) was administered CCl4 and the extract of the actinomycete strain S19 and the 4th group (CCl4+G30) received CCl4 and the extract of the actinomycete strain G30, both treatments for 8 weeks. The results revealed that the two actinomycete extracts S19 and G30 could significantly (p < 0.01) lower the elevated levels of serum creatinine, urea, and uric acid caused by the CCl4 administration. Additionally, the two actinomycete extracts improved the decreased serum total protein. Interestingly, treatment of the CCl4-intoxicated rats with S19 and G30 extracts remarkably reversed the lowered renal glutathione (GSH), glutathione peroxidase (GSH-Px), peroxidase (Px) and superoxide dismutase (SOD) activities, and the elevated lipid peroxidation (LPO) levels. The histopathological examination of the treated kidney revealed that the two actinomycete extracts improved rats against CCl4-induced kidney lesions. The present results suggested that the protective effect of the two actinomycete extracts may rely on its effect on reducing the oxidative stress and improving the antioxidant defense system.

International Journal of Systematic and Evolutionary Microbiology

A Gram-stain-negative, aerobic, rod-shaped bacterium, designated strain C8-1, was isolated from t... more A Gram-stain-negative, aerobic, rod-shaped bacterium, designated strain C8-1, was isolated from the rhizosphere soil of Nicotiana tabacum L. collected from Kunming, south-west China. The cells showed oxidase-positive and catalase-positive reactions. Growth was observed at 10-40 °C, at pH 6.0-8.0 and in the presence of up to 1 % (w/v) NaCl, with optimal growth at 30 °C and pH 7.0. The predominant isoprenoid quinone was Q-8. The major fatty acids were identified as iso-C15 : 0, iso-C17 : 0 and iso-C17 : 1ω9c. The cellular polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine, five unidentified phospholipids and two unidentified aminophospholipids. The genomic DNA G+C content was 70.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain C8-1 should be assigned to the genus Lysobacter. 16S rRNA gene sequence similarity analysis showed that strain C8-1 was closely related to Lysobacter cavernae YIM C01544 (98.6 %), Lysobacter soli DCY21 (97.6 %), Lysobacter panacisoli CJ29 (97.3 %), Lysobacter firmicutimachus PB-6250 (97.3 %), Lysobacter niastensis GH41-7 (97.3 %) and Lysobacter gummosus KCTC 12132 (97.1 %). DNA-DNA hybridization data indicated that the isolate may represent a novel genomic species belonging to the genus Lysobacter. Polyphasic taxonomic characteristics indicated that strain C8-1 represents a novel species of the genus Lysobacter, for which the name Lysobacter tabacisoli sp. nov. is proposed. The type strain is C8-1 (=KCTC 62034=CGMCC 1.16271) .

Archives of Microbiology

A Gram-positive and aerobic actinobacterium, strain SYSU D8006, was isolated from a desert sand s... more A Gram-positive and aerobic actinobacterium, strain SYSU D8006, was isolated from a desert sand sample collected from Gurbantunggut desert, China. Phenotypically, the strain was found to grow at 14-50 °C, pH 6.0-9.0 and in the presence of up to 4% (w/v) NaCl. The chemotaxonomic features of strain SYSU D8006 included menaquinone MK-9(H) as the respiratory quinone, diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannoside as known polar lipids, iso-C iso-C C ω8c and C ω9c as the predominant fatty acids, and arabinose, galactose and glucose as the whole cell sugars. Strain SYSU D8006 shared the highest 16S rRNA gene sequence identity with Blastococcus jejuensis DSM 19597 (98.2%). Based on the analyses of the phenotypic, genotypic and phylogenetic characteristics, strain SYSU D8006 is characterized to represent a novel species of the genus Blastococcus, for which the name Blastococcus deserti sp. nov. is proposed. The type strain is SYSU D8006 (= CGMCC 1.15935 = KCTC 49026 = CPCC 204618).

International journal of systematic and evolutionary microbiology, 2018

A novel strain, designated Y1A-10 4-9-1, with Gram-stain-positive and rod-shaped cells, was isola... more A novel strain, designated Y1A-10 4-9-1, with Gram-stain-positive and rod-shaped cells, was isolated from paddy soil in Yingtan, Jiangxi, China. Cells were 0.15-0.2 µm wide and 1.5-3.3 µm long. The optimal growth temperature was 30 °C and the optimal pH was 7.0. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the novel strain is closely related to Propionicimonas paludicola JCM 11933 (98.57 %). The genomic DNA G+C content was 63.9 mol%. The predominant menaquinone was MK-9(H4) and meso-diaminopimelic acid was present in the cell-wall peptidoglycan layer. The major polar lipids were diphosphatidylglycerol, one unidentified phospholipid and two unidentified lipids. The dominant cellular fatty acids detected were anteiso-C15 : 0 and iso-C16 : 0. The phylogenetic and phenotypic results supported that strain Y1A-10 4-9-1 is a novel species of the genus Propionicimonas, for which the name Propionicimonas ferrireducens sp. nov. is proposed. The type strain is Y1A-10 4...

Antonie van Leeuwenhoek, Jan 17, 2018

A gene encoding a β-xylosidase (designated as Thxyl43A) was cloned from strain Thermobifida halot... more A gene encoding a β-xylosidase (designated as Thxyl43A) was cloned from strain Thermobifida halotolerans YIM 90462. The open reading frame of this gene encodes 550 amino acid residues. The gene was over-expressed in Escherichia coli and the recombinant protein was purified. The monomeric Thxyl43A protein presented a molecular mass of 61.5 kDa. When p-nitrophenyl-β-d-xylopyranoside was used as the substrate, recombinant Thxyl43A exhibited optimal activity at 55 °C and pH 4.0 to 7.0, being thermostable by maintaining 47% of its activity after 30 h incubation at 55 °C. The recombinant enzyme retained more than 80% residual activity after incubation at pH range of 4.0 to 12.0 for 24 h, respectively, which indicated notable thermostability and pH stability of Thxyl43A. Moreover, Thxyl43A displayed high catalytic activity (> 60%) in presence of 5-35% NaCl (w/v) or 1-20% ionic liquid (w/v) or 1-50 mM xylose. These properties suggest that Thxyl43A has potential for promoting hemicellulos...