Garima Arya - Academia.edu (original) (raw)
Papers by Garima Arya
Molecular Microbiology
Several GntR/FadR transcriptional regulators govern sugar acid metabolism in bacteria. Although e... more Several GntR/FadR transcriptional regulators govern sugar acid metabolism in bacteria. Although effectors have been identified for a few sugar acid regulators, the mode of effector binding is unknown. Even in the overall FadR subfamily, there are limited details on effectorregulator interactions. Here, we identified the effector-binding cavity in Escherichia coli DgoR, a FadR subfamily transcriptional repressor of D-galactonate metabolism that employs D-galactonate as its effector. Using a genetic screen, we isolated several dgoR superrepressor alleles. Blind docking suggested eight amino acids corresponding to these alleles to form a part of the effector-binding cavity. In vivo and in vitro assays showed that these mutations compromise the inducibility of DgoR without affecting its oligomeric status or affinity for target DNA. Taking Bacillus subtilis GntR as a representative, we demonstrated that the effector-binding cavity is similar amongst FadR subfamily sugar acid regulators. Finally, a comparison of sugar acid regulators with other FadR members suggested conserved features of effector-regulator recognition within the FadR subfamily. Sugar acid metabolism is widely implicated in bacterial colonization and virulence. The present study sets the basis to investigate the influence of natural genetic variations in FadR subfamily regulators on their sensitivity to sugar acids and ultimately on host-bacterial interactions.
This review article is a synthesis of biodegraded indoor environments contain a complex mixture o... more This review article is a synthesis of biodegraded indoor environments contain a complex mixture of live (viable) and dead (nonviable) microorganisms, fragments thereof, toxins, allergens, volatile microbial organic compounds and other chemicals. The indoor concentrations of some of these organisms and agents are known or suspected to be elevated in biodegraded indoor environments and may affect the health of people living or working there in. Asthma, asthmatic symptoms and allergic sensitization are linked with a number of indoor exposures, such as volatile organic compounds (VOCs), phthalates, tobacco smoke and biological agents. This review focuses solely on the biological exposures. Exposures to allergens, microbial agents and other biological particles are risk factors to these health effects, but the exact causal connections or the mechanisms underlying the symptoms are still not well understood. Among the open questions come the importance of geneticenvironmental interactions ...
According to Bergey s Manual of Systematic Bacteriology volume IV, the actinomycetes are Gram pos... more According to Bergey s Manual of Systematic Bacteriology volume IV, the actinomycetes are Gram positive filamentous bacteria having G+C (<55%) content in their DNA. The name actinomycete was derived from Greek word aktis (a ray) and mykes (fungus). The actinomycetes are most widely distributed group of microbial consortia found in nature which primarily inhabit the soil (Manjula et al., 2009). These have been reported to be most common antibiotic producing microorganisms found in soil. Actinomycetes provided about two third part (more than 4,000) naturally occurring antibiotics discovered including many of those important in medicine such as aminoglycoside, actinomycin, anthracycline, lactam, chloramphnicol, macroides, peptides and tetracycline (Wakesman, 1968). These bioactive compounds have highly commercial value and continue to be routinely screened for new bioactive compounds. Almost 80% of the world s antibiotics are known to come from actinomycetes mostly from the genera St...
International Journal of Current Microbiology and Applied Sciences, 2019
Journal of Drug Delivery and Therapeutics, 2016
Statistical analysis of Actinomycetes isolated from biodegraded and non biodegraded building mate... more Statistical analysis of Actinomycetes isolated from biodegraded and non biodegraded building materials at Haridwar region of Uttarakhand (India). The concentrations of viable actinomycetes varied between 50-250 x10 4 and 5-150x10 4 cfu/g in the biodegradable and non degradable buildings, respectively. In all studies, the concentrations of viable actinomycetes were higher in the index (biodegradable) buildings than in the reference (non biodegradable) buildings. Phylogenetic characterization of the isolates based on 16S rRNA gene sequencing supported their assignment to 18 different actinomycete genera representing seven different suborders. The result exhibited similarity 91% with 10 strains from the uncultured known species of Streptomyces, Nocardia and Micromonospora. The 16S rRNA nucleotide sequence of Streptomyces, Nocardia and Micromonospora consisted of 749 bp each and the G-C content was 70%. These results show a high diversity of actinomycetes associated with buiding materials and the detection and identification of this group of organisms is extremely important for the deteriogenic process and the development of control methods.
Journal of Drug Delivery and Therapeutics, 2016
To predict the mathematical isopleths model for the growth of fungal mycelium in building materia... more To predict the mathematical isopleths model for the growth of fungal mycelium in building material. The mould fungal growth is one of the first signs of biological growth linked to relative humidity and temperature condition in buildings materials. The numerical growth model was based on several models are found in literature. Quantification of fungal growth in the model is based on mould index used in the experiments for visual inspection. This model consists of differential equations describe the growth rate of the fungal growth index in vary fluctuating conditions including the effect of exposure time, temperature, relative humidity and dryness. Up to now the mathematical isopleth model to assess the fungal mould growth which is based on steady boundary conditions. This study presented new results for mathematical isopleth of mould growth on the surface of building materials such as wood, cement, concrete.
Journal of Drug Delivery and Therapeutics, 2016
A mathematical model for the growth of filamentous microorganisms has been tested by comparison o... more A mathematical model for the growth of filamentous microorganisms has been tested by comparison of model predictions with data on growth of Streptomyces on building wood material. Growth of Streptomyces resulted in movement of filament classes to increasing the size, while shear forces produced mycelial fragments which entered the smallest size class, from which they grew to form further colonies on building surface materials. Quantification of Streptomyces growth in the model is based on the mould index used in the experiments for visual inspection. The model consists of differential equations describing the growth rate of the mould index in different fuctuating conditions including the effect of exposure time, temperature, relative humidity and dry periods. Temperature and humidity conditions favourable for mould growth are presented as a mathematical model. The modified model generated predictions which agreed closely with experimental data on biomass concentration, distribution, number of colonies and colonies radius during their growth on building wood material, thereby supporting the assumptions on which the model was based. The numerical values of the parameters included in the model are fitted for pine and spruce sapwood, but the functional form of the model can be reasoned to be valid also for other wood-based materials.
Journal of Drug Delivery and Therapeutics, 2012
International Journal For Science Technology And Engineering, 2016
Religious building materials are often renovated with a high expenditure of time and money withou... more Religious building materials are often renovated with a high expenditure of time and money without investigating and considering the causes of either damages or deterioration. In many ways, religious buildings can only be maintained by changing their usage. This change of use may influence the interior climate enormously. To assess the effect on the risk of fungal mycelial growth on building parts or building materials, a predictive model has been developed recently, describing the hydrothermal behaviour of the spore. It allows for the first time to employ the changing surface temperatures and relative humidity for the computational prediction of fungal mycelial growth. The calculational assessment of fungal growth allows the handling of such problems which until now could not be solved with simple estimations or with reasonable metrological expense. The modified model generated predictions which agreed closely with experimental data on fungal mycelia growth on religious building ma...
Molecular Microbiology
Several GntR/FadR transcriptional regulators govern sugar acid metabolism in bacteria. Although e... more Several GntR/FadR transcriptional regulators govern sugar acid metabolism in bacteria. Although effectors have been identified for a few sugar acid regulators, the mode of effector binding is unknown. Even in the overall FadR subfamily, there are limited details on effectorregulator interactions. Here, we identified the effector-binding cavity in Escherichia coli DgoR, a FadR subfamily transcriptional repressor of D-galactonate metabolism that employs D-galactonate as its effector. Using a genetic screen, we isolated several dgoR superrepressor alleles. Blind docking suggested eight amino acids corresponding to these alleles to form a part of the effector-binding cavity. In vivo and in vitro assays showed that these mutations compromise the inducibility of DgoR without affecting its oligomeric status or affinity for target DNA. Taking Bacillus subtilis GntR as a representative, we demonstrated that the effector-binding cavity is similar amongst FadR subfamily sugar acid regulators. Finally, a comparison of sugar acid regulators with other FadR members suggested conserved features of effector-regulator recognition within the FadR subfamily. Sugar acid metabolism is widely implicated in bacterial colonization and virulence. The present study sets the basis to investigate the influence of natural genetic variations in FadR subfamily regulators on their sensitivity to sugar acids and ultimately on host-bacterial interactions.
This review article is a synthesis of biodegraded indoor environments contain a complex mixture o... more This review article is a synthesis of biodegraded indoor environments contain a complex mixture of live (viable) and dead (nonviable) microorganisms, fragments thereof, toxins, allergens, volatile microbial organic compounds and other chemicals. The indoor concentrations of some of these organisms and agents are known or suspected to be elevated in biodegraded indoor environments and may affect the health of people living or working there in. Asthma, asthmatic symptoms and allergic sensitization are linked with a number of indoor exposures, such as volatile organic compounds (VOCs), phthalates, tobacco smoke and biological agents. This review focuses solely on the biological exposures. Exposures to allergens, microbial agents and other biological particles are risk factors to these health effects, but the exact causal connections or the mechanisms underlying the symptoms are still not well understood. Among the open questions come the importance of geneticenvironmental interactions ...
According to Bergey s Manual of Systematic Bacteriology volume IV, the actinomycetes are Gram pos... more According to Bergey s Manual of Systematic Bacteriology volume IV, the actinomycetes are Gram positive filamentous bacteria having G+C (<55%) content in their DNA. The name actinomycete was derived from Greek word aktis (a ray) and mykes (fungus). The actinomycetes are most widely distributed group of microbial consortia found in nature which primarily inhabit the soil (Manjula et al., 2009). These have been reported to be most common antibiotic producing microorganisms found in soil. Actinomycetes provided about two third part (more than 4,000) naturally occurring antibiotics discovered including many of those important in medicine such as aminoglycoside, actinomycin, anthracycline, lactam, chloramphnicol, macroides, peptides and tetracycline (Wakesman, 1968). These bioactive compounds have highly commercial value and continue to be routinely screened for new bioactive compounds. Almost 80% of the world s antibiotics are known to come from actinomycetes mostly from the genera St...
International Journal of Current Microbiology and Applied Sciences, 2019
Journal of Drug Delivery and Therapeutics, 2016
Statistical analysis of Actinomycetes isolated from biodegraded and non biodegraded building mate... more Statistical analysis of Actinomycetes isolated from biodegraded and non biodegraded building materials at Haridwar region of Uttarakhand (India). The concentrations of viable actinomycetes varied between 50-250 x10 4 and 5-150x10 4 cfu/g in the biodegradable and non degradable buildings, respectively. In all studies, the concentrations of viable actinomycetes were higher in the index (biodegradable) buildings than in the reference (non biodegradable) buildings. Phylogenetic characterization of the isolates based on 16S rRNA gene sequencing supported their assignment to 18 different actinomycete genera representing seven different suborders. The result exhibited similarity 91% with 10 strains from the uncultured known species of Streptomyces, Nocardia and Micromonospora. The 16S rRNA nucleotide sequence of Streptomyces, Nocardia and Micromonospora consisted of 749 bp each and the G-C content was 70%. These results show a high diversity of actinomycetes associated with buiding materials and the detection and identification of this group of organisms is extremely important for the deteriogenic process and the development of control methods.
Journal of Drug Delivery and Therapeutics, 2016
To predict the mathematical isopleths model for the growth of fungal mycelium in building materia... more To predict the mathematical isopleths model for the growth of fungal mycelium in building material. The mould fungal growth is one of the first signs of biological growth linked to relative humidity and temperature condition in buildings materials. The numerical growth model was based on several models are found in literature. Quantification of fungal growth in the model is based on mould index used in the experiments for visual inspection. This model consists of differential equations describe the growth rate of the fungal growth index in vary fluctuating conditions including the effect of exposure time, temperature, relative humidity and dryness. Up to now the mathematical isopleth model to assess the fungal mould growth which is based on steady boundary conditions. This study presented new results for mathematical isopleth of mould growth on the surface of building materials such as wood, cement, concrete.
Journal of Drug Delivery and Therapeutics, 2016
A mathematical model for the growth of filamentous microorganisms has been tested by comparison o... more A mathematical model for the growth of filamentous microorganisms has been tested by comparison of model predictions with data on growth of Streptomyces on building wood material. Growth of Streptomyces resulted in movement of filament classes to increasing the size, while shear forces produced mycelial fragments which entered the smallest size class, from which they grew to form further colonies on building surface materials. Quantification of Streptomyces growth in the model is based on the mould index used in the experiments for visual inspection. The model consists of differential equations describing the growth rate of the mould index in different fuctuating conditions including the effect of exposure time, temperature, relative humidity and dry periods. Temperature and humidity conditions favourable for mould growth are presented as a mathematical model. The modified model generated predictions which agreed closely with experimental data on biomass concentration, distribution, number of colonies and colonies radius during their growth on building wood material, thereby supporting the assumptions on which the model was based. The numerical values of the parameters included in the model are fitted for pine and spruce sapwood, but the functional form of the model can be reasoned to be valid also for other wood-based materials.
Journal of Drug Delivery and Therapeutics, 2012
International Journal For Science Technology And Engineering, 2016
Religious building materials are often renovated with a high expenditure of time and money withou... more Religious building materials are often renovated with a high expenditure of time and money without investigating and considering the causes of either damages or deterioration. In many ways, religious buildings can only be maintained by changing their usage. This change of use may influence the interior climate enormously. To assess the effect on the risk of fungal mycelial growth on building parts or building materials, a predictive model has been developed recently, describing the hydrothermal behaviour of the spore. It allows for the first time to employ the changing surface temperatures and relative humidity for the computational prediction of fungal mycelial growth. The calculational assessment of fungal growth allows the handling of such problems which until now could not be solved with simple estimations or with reasonable metrological expense. The modified model generated predictions which agreed closely with experimental data on fungal mycelia growth on religious building ma...