Acidithiobacillus ferrianus sp. nov.: an ancestral extremely acidophilic and facultatively anaerobic chemolithoautotroph (original) (raw)
Related papers
Advanced Materials Research, 2009
It has long been recognized that isolates of iron-and sulfur-oxidizing acidophiles referred to as "Acidithiobacillus ferrooxidans" probably include more than one species, on the basis of differences in chromosomal GC contents and 16S rRNA gene sequences. Phylogenetic heterogeneity among these isolates was confirmed by phylogenetic analysis using the sequences of the 16S-23S intergenic spacers (ITS). Two main groups have been identified: the first includes the type strain of Acidithiobacillus ferrooxidans and a second comprises a cluster of newly isolated strains that have 98.5% 16S rRNA gene sequence identity with the type strain. Given that the new group of isolates have GC contents of 56 mol% as opposed to 58.8 mol% for At. ferrooxidans T , and that they share only 37% homologous DNA, these were given the new species name Acidithiobacillus ferrivorans. Further studies showed that, while strains of At. ferrivorans have many physiological traits in common with At. ferrooxidans, they also differ in some key characteristics. These include the ability to grow at temperatures as low as 4°C (as opposed to the lower limit of between 10 and 12°C for At. ferrooxidans) and the greater sensitivity of At. ferrivorans to low pH (minimum of 1.9 for growth as opposed to 1.3 for At. ferrooxidans T ). Important genotypic differences include the fact that all strains of At. ferrivorans do not contain the archetypal rusticyanin gene (rusA), rather most contain a rusA homologue (rusB). Furthermore, the high potential iron-sulfur protein-encoding gene of all At. ferrivorans strains analyzed is more similar to the iro than to the hip gene characterized in At. ferrooxidans T . These results suggest that the iron oxidation pathways are different in At. ferrivorans and At. ferrooxidans.
Microbiology, 2010
Autotrophic acidophilic iron- and sulfur-oxidizing bacteria of the genus Acidithiobacillus constitute a heterogeneous taxon encompassing a high degree of diversity at the phylogenetic and genetic levels, though currently only two species are recognized (Acidithiobacillus ferrooxidans and Acidithiobacillus ferrivorans). One of the major functional disparities concerns the biochemical mechanisms of iron and sulfur oxidation, with discrepancies reported in the literature concerning the genes and proteins involved in these processes. These include two types of high-potential iron–sulfur proteins (HiPIPs): (i) Iro, which has been described as the iron oxidase; and (ii) Hip, which has been proposed to be involved in the electron transfer between sulfur compounds and oxygen. In addition, two rusticyanins have been described: (i) rusticyanin A, encoded by the rusA gene and belonging to the well-characterized rus operon, which plays a central role in the iron respiratory chain; and (ii) rust...
Extremophiles, 2009
Phenotypic and genotypic analysis was carried out on four iron-and sulfur-oxidizing acidophilic bacteria (the ''NO-37 group'') isolated from different parts of the world. 16S rRNA phylogeny showed that they are highly related to each other, but are less related to the type strain of Acidithiobacillus ferrooxidans. The NO-37 group isolates are obligate chemolithoautotrophs, facultative anaerobes, diazotrophic, and psychrotolerant. They are less tolerant of extremely low pH, and in contrast to At. ferrooxidans T , all of the NO-37 group isolates are motile. The GC contents of genomic DNA of the NO-37 group isolates were around 56 mol% and the DNA-DNA hybridization value between genomic DNA of isolate NO-37 and At. ferrooxidans T was 37%. It also appears that the bacteria of the NO-37 group have a different biochemical mechanism for oxidizing ferrous iron than At. ferrooxidans T ; the gene coding for the archetypal rusticyanin (RusA) was not detected in any of the NO-37 group isolates, rather a gene coding for a homologous protein (RusB) was amplified from three of the four novel isolates. Isolates of the NO-37 group clearly belong to a species that is different to those already recognized in the genus Acidithiobacillus, for which the name Acidithiobacillus ferrivorans is proposed. Keywords Acid mine drainage Á Acidophile Á Acidithiobacillus Á Bioleaching Á Biomining Á Iron Á Pyrite Á Psychrotolerant bacteria Á Sulfur Communicated by T. Matsunaga.
International Journal of Systematic and Evolutionary Microbiology, 2013
Twelve strains of iron-oxidizing acidithiobacilli isolated from acidic sites throughout the world, including some previously shown by multi-locus sequence analyses and DNA–DNA hybridization to comprise a distinct species, were characterized in terms of their physiologies. The bacteria were shown to be obligately chemolithotrophic, acidophilic and mesophilic, and grew in both oxic and anoxic environments, using ferrous iron, reduced sulfur or hydrogen as electron donors and oxygen or ferric iron as electron acceptors. Some of the strains grew at lower pH than those reported for the two recognized iron-oxidizing Acidithiobacillus species, Acidithiobacillus ferrooxidans and Acidithiobacillus ferrivorans . Tolerance of transition metals and aluminium, and also specific rates of iron oxidation and reduction, were more similar to those of A. ferrooxidans (to which the strains are more closely related) than to A. ferrivorans . The name Acidithiobacillus ferridurans sp. nov. is proposed to ...
Frontiers in microbiology, 2017
The iron-oxidizing species Acidithiobacillus ferrivorans is one of few acidophiles able to oxidize ferrous iron and reduced inorganic sulfur compounds at low temperatures (<10°C). To complete the genome of At. ferrivorans strain CF27, new sequences were generated, and an update assembly and functional annotation were undertaken, followed by a comparative analysis with other Acidithiobacillus species whose genomes are publically available. The At. ferrivorans CF27 genome comprises a 3,409,655 bp chromosome and a 46,453 bp plasmid. At. ferrivorans CF27 possesses genes allowing its adaptation to cold, metal(loid)-rich environments, as well as others that enable it to sense environmental changes, allowing At. ferrivorans CF27 to escape hostile conditions and to move toward favorable locations. Interestingly, the genome of At. ferrivorans CF27 exhibits a large number of genomic islands (mostly containing genes of unknown function), suggesting that a large number of genes has been acqu...
Scientific Reports
Acidithiobacillus ferrooxidans, a chemolithoautotrophic bacterium, is well known for its mineral oxidizing properties. The current study combines experimental and whole genome sequencing approaches to investigate an iron oxidizing, extreme acidophilic bacterium, A. ferrooxidans isolate (IO-2C) from an acid seep area near Carlos, TX, USA. Strain IO-2C was capable of oxidizing iron i.e. iron sulphate and iron ammonium sulphate yielding shwertmannite and jarosite minerals. Further, the bacterium’s genome was sequenced, assembled and annotated to study its general features, structure and functions. To determine genetic heterogeneity, it was compared with the genomes of other published A. ferrooxidans strains. Pan-genome analysis displayed low gene conservation and significant genetic diversity in A. ferrooxidans species comprising of 6926 protein coding sequences with 23.04% (1596) core genes, 46.13% (3195) unique and 30.82% (2135) accessory genes. Variant analysis showed >75,000 var...
1992
A heterotrophic bacterium, isolated from an acidic stream in a disused pyrite mine which contained copious growths of "acid streamers," displayed characteristics which differentiated it from previously described mesophilic acidophiles. The isolate was obligately acidophilic, with a pH range of 2.0 to 4.4 and an optimum pH of 3.0. The bacterium was unable to fix carbon dioxide but oxidized ferrous iron, although at a slower rate than either Thiobacilusferrooxidans or LeptospiriUllumferrooxidans. Elemental sulfur and manganese(II) were not oxidized. In liquid media, the isolate produced macroscopic streamerlike growths. Microscopic examination revealed that the bacterium formed long (>100 p,m) filaments which tended to disintegrate during later
Genetic variability in Acidithiobacillus spp. – a working horse of environmental biotechnologies
Nova Biotechnologica et Chimica, 2018
The genus Acidithiobacillus comprises 7 species of Gram-negative obligatory acidophilic chemolithotrophic bacteria that derive energy mainly from the oxidation of reduced sulphur compounds. Four of the species also catalyse the dissimilatory oxidation of ferrous iron while three (A. thiooxidans, A. albertensis, and A. caldus) do not. Bacteria from the genus Acidithiobacillus are often associated with mineral biotechnologies (biomining) and acid mine drainage. While acceleration of mineral solubilisation is a positive aspect in environmental biotechnologies, it is undesirable in acid mine drainage with strong negative ecological impact and there is profound interest in genetics and genomics of these bacteria. Representatives of Acidithiobacillus genus occur world-wide, however there are limited data on Acidithiobacillus spp. variability from Slovakia. In our work the variability of Acidithiobacillus spp., from Slovakia was analysed and the presence of A ferrooxidans was detected. In ...
Frontiers in microbiology, 2017
The acidithiobacilli are sulfur-oxidizing acidophilic bacteria that thrive in both natural and anthropogenic low pH environments. They contribute to processes that lead to the generation of acid rock drainage in several different geoclimatic contexts, and their properties have long been harnessed for the biotechnological processing of minerals. Presently, the genus is composed of seven validated species, described between 1922 and 2015: Acidithiobacillus thiooxidans, A. ferrooxidans, A. albertensis, A. caldus, A. ferrivorans, A. ferridurans, and A. ferriphilus. However, a large number of Acidithiobacillus strains and sequence clones have been obtained from a variety of ecological niches over the years, and many isolates are thought to vary in phenotypic properties and cognate genetic traits. Moreover, many isolates remain unclassified and several conflicting specific assignments muddle the picture from an evolutionary standpoint. Here we revise the phylogenetic relationships within ...