# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 581 | 0 | 0.9821 | Inorganic polyphosphates and heavy metal resistance in microorganisms. The mechanisms of heavy metal resistance in microbial cells involve multiple pathways. They include the formation of complexes with specific proteins and other compounds, the excretion from the cells via plasma membrane transporters in case of procaryotes, and the compartmentalization of toxic ions in vacuoles, cell wall and other organelles in case of eukaryotes. The relationship between heavy metal tolerance and inorganic polyphosphate metabolism was demonstrated both in prokaryotic and eukaryotic microorganisms. Polyphosphates, being polyanions, are involved in detoxification of heavy metals through complex formation and compartmentalization. The bacteria and fungi cultivated in the presence of some heavy metal cations contain the enhanced levels of polyphosphate. In bacteria, polyphosphate sequesters heavy metals; some of metal cations stimulate an exopolyphosphatase activity, which releases phosphate from polyphosphates, and MeHPO(4)(-) ions are then transported out of the cells. In fungi, the overcoming of heavy metal stresses is associated with the accumulation of polyphosphates in cytoplasmic inclusions, vacuoles and cell wall and the formation of cation/polyphosphate complexes. The effects of knockout mutations and overexpression of the genes encoding polyphosphate-metabolizing enzymes on heavy metal resistance are discussed. | 2018 | 30151754 |
| 343 | 1 | 0.9818 | Cloning and molecular characterization of three arylamine N-acetyltransferase genes from Bacillus anthracis: identification of unusual enzymatic properties and their contribution to sulfamethoxazole resistance. The arylamine N-acetyltransferases (NATs) are xenobiotic-metabolizing enzymes that catalyze the N-acetylation of arylamines and their N-hydroxylated metabolites. These enzymes play a key role in detoxication of numerous drugs and xenobiotics. We report here the cloning, functional expression, and characterization of three new NAT genes (termed banatA, banatB, and banatC) from the pathogen Bacillus anthracis. The sequences of the corresponding proteins are approximately 30% identical with those of characterized eukaryotic and prokaryotic NAT enzymes, and the proteins were recognized by an anti-NAT antibody. The three genes were endogenously expressed in B. anthracis, and NAT activity was found in cell extracts. The three NAT homologues exhibited distinct structural and enzymatic properties, some of which have not previously been observed with other NAT enzymes. Recombinant BanatC displayed strong NAT activity toward several prototypic NAT substrates, including the sulfonamide antibiotic sulfamethoxazole (SMX). As opposed to BanatC, BanatB also had acetyl-CoA (AcCoA) and p-nitrophenyl acetate (PNPA) hydrolysis activity in the absence of arylamine substrates, indicating that it may act as an AcCoA hydrolase. BanatA was devoid of NAT or AcCoA/PNPA hydrolysis activities, suggesting that it may be a new bacterial NAT-like protein with unknown function. Expression of BanatC in Escherichia coli afforded higher-than-normal resistance to SMX in the recombinant bacteria, whereas an inactive mutant of the enzyme did not. These data indicate that BanatC could contribute to the resistance of B. anthracis to SMX. | 2007 | 17511472 |
| 8543 | 2 | 0.9815 | Soil bacteria, genes, and metabolites stimulated during sulfur cycling and cadmium mobilization under sodium sulfate stress. Sodium sulfate stress is known to improve cadmium (Cd) mobilization in soil and microbial sulfur oxidation, Cd resistance, and the accumulation of stress tolerance-associated metabolites has been correlated with increased soil Cd availability and toxicity. In this study, aerobic soil microcosms with Cd-contamination were stimulated with sodium sulfate to investigate its effects on soil microbial community structure, functional genes, and associated metabolite profiles. Metagenomic analysis revealed that sulfur oxidizing and Cd-resistant bacteria carried gene clusters encoding sox, dsr, and sqr genes, and znt, czc, and cad genes, respectively. Exposure to sodium sulfate resulted in the reprogram of soil metabolites. In particular, intensification of sulfur metabolism triggered an up-regulation in the tricarboxylic acid (TCA) cycle, which promoted the secretion of carboxylic acids and their precursors by soil bacteria. The accumulation of organic acids induced in response to high sodium sulfate dosages potentially drove an observed increase in Cd mobility. Pseudomonas and Erythrobacter spp. exhibited a high capacity for adaptation to heavy metal- or sulfur-induced stress, evident by an increased abundance of genes and metabolites for sulfur cycling and Cd resistance. These results provide valuable insights towards understanding the microbial mechanisms of sulfur transformation and Cd dissolution under saline stress. | 2021 | 34214562 |
| 191 | 3 | 0.9812 | Mariprofundus ferrooxydans PV-1 the first genome of a marine Fe(II) oxidizing Zetaproteobacterium. Mariprofundus ferrooxydans PV-1 has provided the first genome of the recently discovered Zetaproteobacteria subdivision. Genome analysis reveals a complete TCA cycle, the ability to fix CO(2), carbon-storage proteins and a sugar phosphotransferase system (PTS). The latter could facilitate the transport of carbohydrates across the cell membrane and possibly aid in stalk formation, a matrix composed of exopolymers and/or exopolysaccharides, which is used to store oxidized iron minerals outside the cell. Two-component signal transduction system genes, including histidine kinases, GGDEF domain genes, and response regulators containing CheY-like receivers, are abundant and widely distributed across the genome. Most of these are located in close proximity to genes required for cell division, phosphate uptake and transport, exopolymer and heavy metal secretion, flagellar biosynthesis and pilus assembly suggesting that these functions are highly regulated. Similar to many other motile, microaerophilic bacteria, genes encoding aerotaxis as well as antioxidant functionality (e.g., superoxide dismutases and peroxidases) are predicted to sense and respond to oxygen gradients, as would be required to maintain cellular redox balance in the specialized habitat where M. ferrooxydans resides. Comparative genomics with other Fe(II) oxidizing bacteria residing in freshwater and marine environments revealed similar content, synteny, and amino acid similarity of coding sequences potentially involved in Fe(II) oxidation, signal transduction and response regulation, oxygen sensation and detoxification, and heavy metal resistance. This study has provided novel insights into the molecular nature of Zetaproteobacteria. | 2011 | 21966516 |
| 6388 | 4 | 0.9811 | A Metagenome from a Steam Vent in Los Azufres Geothermal Field Shows an Abundance of Thermoplasmatales archaea and Bacteria from the Phyla Actinomycetota and Pseudomonadota. Los Azufres National Park is a geothermal field that has a wide number of thermal manifestations; nevertheless, the microbial communities in many of these environments remain unknown. In this study, a metagenome from a sediment sample from Los Azufres National Park was sequenced. In this metagenome, we found that the microbial diversity corresponds to bacteria (Actinomycetota, Pseudomonadota), archaea (Thermoplasmatales and Candidatus Micrarchaeota and Candidatus Parvarchaeota), eukarya (Cyanidiaceae), and viruses (Fussellovirus and Caudoviricetes). The functional annotation showed genes related to the carbon fixation pathway, sulfur metabolism, genes involved in heat and cold shock, and heavy-metal resistance. From the sediment, it was possible to recover two metagenome-assembled genomes from Ferrimicrobium and Cuniculiplasma. Our results showed that there are a large number of microorganisms in Los Azufres that deserve to be studied. | 2023 | 37504286 |
| 8425 | 5 | 0.9809 | Carotenoid biosynthesis in extremophilic Deinococcus-Thermus bacteria. Bacteria from the phylum Deinococcus-Thermus are known for their resistance to extreme stresses including radiation, oxidation, desiccation and high temperature. Cultured Deinococcus-Thermus bacteria are usually red or yellow pigmented because of their ability to synthesize carotenoids. Unique carotenoids found in these bacteria include deinoxanthin from Deinococcus radiodurans and thermozeaxanthins from Thermus thermophilus. Investigations of carotenogenesis will help to understand cellular stress resistance of Deinococcus-Thermus bacteria. Here, we discuss the recent progress toward identifying carotenoids, carotenoid biosynthetic enzymes and pathways in some species of Deinococcus-Thermus extremophiles. In addition, we also discuss the roles of carotenoids in these extreme bacteria. | 2010 | 20832321 |
| 584 | 6 | 0.9807 | Cadmium and iron transport by members of a plant metal transporter family in Arabidopsis with homology to Nramp genes. Metal cation homeostasis is essential for plant nutrition and resistance to toxic heavy metals. Many plant metal transporters remain to be identified at the molecular level. In the present study, we have isolated AtNramp cDNAs from Arabidopsis and show that these genes complement the phenotype of a metal uptake deficient yeast strain, smf1. AtNramps show homology to the Nramp gene family in bacteria, yeast, plants, and animals. Expression of AtNramp cDNAs increases Cd(2+) sensitivity and Cd(2+) accumulation in yeast. Furthermore, AtNramp3 and AtNramp4 complement an iron uptake mutant in yeast. This suggests possible roles in iron transport in plants and reveals heterogeneity in the functional properties of Nramp transporters. In Arabidopsis, AtNramps are expressed in both roots and aerial parts under metal replete conditions. Interestingly, AtNramp3 and AtNramp4 are induced by iron starvation. Disruption of the AtNramp3 gene leads to slightly enhanced cadmium resistance of root growth. Furthermore, overexpression of AtNramp3 results in cadmium hypersensitivity of Arabidopsis root growth and increased accumulation of Fe, on Cd(2+) treatment. Our results show that Nramp genes in plants encode metal transporters and that AtNramps transport both the metal nutrient Fe and the toxic metal cadmium. | 2000 | 10781110 |
| 8644 | 7 | 0.9806 | Biotic and abiotic drivers of soil carbon, nitrogen and phosphorus and metal dynamic changes during spontaneous restoration of Pb-Zn mining wastelands. The biotic and abiotic mechanisms that drive important biogeochemical processes (carbon, nitrogen, phosphorus and metals dynamics) in metal mine revegetation remains elusive. Metagenomic sequencing was used to explored vegetation, soil properties, microbial communities, functional genes and their impacts on soil processes during vegetation restoration in a typical Pb-Zn mine. The results showed a clear niche differentiation between bacteria, fungi and archaea. Compared to bacteria and fungi, the archaea richness were more tightly coupled with natural restoration changes. The relative abundances of CAZyme-related, denitrification-related and metal resistance genes reduced, while nitrification, urease, inorganic phosphorus solubilisation, phosphorus transport, and phosphorus regulation -related genes increased. Redundancy analysis, hierarchical partitioning analysis, relative-importance analysis and partial least squares path modelling, indicated that archaea diversity, primarily influenced by available lead, directly impacts carbon dynamics. Functional genes, significantly affected by available cadmium, directly alter nitrogen dynamics. Additionally, pH affects phosphorus dynamics through changes in bacterial diversity, while metal dynamics are directly influenced by vegetation. These insights elucidate natural restoration mechanisms in mine and highlight the importance of archaea in soil processes. | 2025 | 40054196 |
| 524 | 8 | 0.9806 | Sulfamethoxazole degradation by Pseudomonas silesiensis F6a isolated from bioelectrochemical technology-integrated constructed wetlands. The antibiotic-degrading ability and mechanism of the bacteria in the novel and ecological bioelectrochemical technology-integrated constructed wetlands (BICW) remain unknown. In this study, the sulfamethoxazole (SMX) degrading strain Pseudomonas silesiensis F6a (F6a), which had high degradation efficiency, was firstly isolated from a substrate sample in BICW. The SMX degradation process of F6a follows pseudo first order kinetics. Four metabolic pathways and twelve degradation products were identified. Based on genomics and proteomics analysis, six key SMX-degrading genes, Gene4641 deoC, Gene0552 narI, Gene0546 luxS, Gene1753 nuoH, Gene0655 and Gene4650, were identified, which were mainly participated in C-S cleavage, S-N hydrolysis and isoxazole ring cleavage. Interestingly, we found the corresponding sulfonamides resistance genes were not detected in F6a, which may provide an evidence for low abundance of the sulfonamides resistance genes in BICW system. These findings would contribute to a better understanding of biotransformation of antibiotic in the BICW. | 2022 | 35636241 |
| 8672 | 9 | 0.9805 | Pangenomic and functional investigations for dormancy and biodegradation features of an organic pollutant-degrading bacterium Rhodococcus biphenylivorans TG9. Environmental bacteria contain a wealth of untapped potential in the form of biodegradative genes. Leveraging this potential can often be confounded by a lack of understanding of fundamental survival strategies, like dormancy, for environmental stress. Investigating bacterial dormancy-to-degradation relationships enables improvement of bioremediation. Here, we couple genomic and functional assessment to provide context for key attributes of the organic pollutant-degrading strain Rhodococcus biphenylivorans TG9. Whole genome sequencing, pangenome analysis and functional characterization were performed to elucidate important genes and gene products, including antimicrobial resistance, dormancy, and degradation. Rhodococcus as a genus has strong potential for degradation and dormancy, which we demonstrate using R. biphenylivorans TG9 as a model. We identified four Resuscitation-promoting factor (Rpf) encoding genes in TG9 involved in dormancy and resuscitation. We demonstrate that R. biphenylivorans TG9 grows on fourteen typical organic pollutants, and exhibits a robust ability to degrade biphenyl and several congeners of polychlorinated biphenyls. We further induced TG9 into a dormant state and demonstrated pronounced differences in morphology and activity. Together, these results expand our understanding of the genus Rhodococcus and the relationship between dormancy and biodegradation in the presence of environmental stressors. | 2022 | 34688761 |
| 549 | 10 | 0.9805 | Extracytoplasmic function sigma factor σ(D) confers resistance to environmental stress by enhancing mycolate synthesis and modifying peptidoglycan structures in Corynebacterium glutamicum. Mycolates are α-branched, β-hydroxylated, long-chain fatty acid specifically synthesized in bacteria in the suborder Corynebacterineae of the phylum Actinobacteria. They form an outer membrane, which functions as a permeability barrier and confers pathogenic mycobacteria to resistance to antibiotics. Although the mycolate biosynthetic pathway has been intensively studied, knowledge of transcriptional regulation of genes involved in this pathway is limited. Here, we report that the extracytoplasmic function sigma factor σ(D) is a key regulator of the mycolate synthetic genes in Corynebacterium glutamicum in the suborder. Chromatin immunoprecipitation with microarray analysis detected σ(D) -binding regions in the genome, establishing a consensus promoter sequence for σ(D) recognition. The σ(D) regulon comprised acyl-CoA carboxylase subunits, acyl-AMP ligase, polyketide synthase and mycolyltransferases; they were involved in mycolate synthesis. Indeed, deletion or overexpression of sigD encoding σ(D) modified the extractable mycolate amount. Immediately downstream of sigD, rsdA encoded anti-σ(D) and was under the control of a σ(D) -dependent promoter. Another σ(D) regulon member, l,d-transpeptidase, conferred lysozyme resistance. Thus, σ(D) modifies peptidoglycan cross-linking and enhances mycolate synthesis to provide resistance to environmental stress. | 2018 | 29148103 |
| 8535 | 11 | 0.9804 | Metagenomics combined with DNA-based stable isotope probing provide comprehensive insights of active triclosan-degrading bacteria in wastewater treatment. The biotransformation of triclosan (TCS) during wastewater treatment occurred frequently, while little researches are known the identity of microorganisms involved in the biodegradation process. In this work, DNA-based stable isotope probing (DNA-SIP) was occupied to investigate the TCS assimilation microbes originated from a full-scale cyclic activated sludge system in Beijing. Results of TCS removal pathway showed that the TCS removal in nitrification process was mainly contributed by the metabolism of heterotrophic bacteria, accounting for about 18.54%. DNA-SIP assay indicated that Sphingobium dominated the degradation of TCS. Oligotyping analysis further indicated that oligotype GCTAAT and ATGTTA of Sphingobium played important roles in degrading TCS. Furthermore, the Kyoto Encyclopedia of Genes and Genomes functional abundance statistics based on PICRUSt2 showed that glutathione transferase was the most prevalent enzyme involved in TCS metabolism, and TCS might be removed through microbial carbon metabolism. Metagenomics made clear that Sphingobium might play irrelevant role on the propagation of antibiotics resistance genes (ARGs), even though, it could degrade TCS. Thauera and Dechloromonas were identified as the key hosts of most ARGs. This study revealed the potential metabolic pathway and microbial ecology of TCS biodegradation in nitrification process of wastewater treatment system. | 2021 | 33069997 |
| 8269 | 12 | 0.9802 | Molecular genetics of Rhizobium Meliloti symbiotic nitrogen fixation. The application of recombinant DNA techniques to the study of symbiotic nitrogen fixation has yielded a growing list of Rhizobium meliloti genes involved in the processes of nodulation, infection thread formation and nitrogenase activity in nodules on the roots of the host plant, Medicago sativa (alfalfa). Interaction with the plant is initiated by genes encoding sensing and motility systems by which the bacteria recognizes and approaches the root. Signal molecules, such as flavonoids, mediate a complex interplay of bacterial and plant nodulation genes leading to entry of the bacteria through a root hair. As the nodule develops, the bacteria proceed inward towards the cortex within infection threads, the formation of which depends on bacterial genes involved in polysaccharide synthesis. Within the cortex, the bacteria enter host cells and differentiate into forms known as bacteroids. Genes which encode and regulate nitrogenase enzyme are expressed in the mature nodule, together with other genes required for import and metabolism of carbon and energy sources offered by the plant. | 1989 | 14542173 |
| 8620 | 13 | 0.9802 | Changes in Microbiome Confer Multigenerational Host Resistance after Sub-toxic Pesticide Exposure. The gut is a first point of contact with ingested xenobiotics, where chemicals are metabolized directly by the host or microbiota. Atrazine is a widely used pesticide, but the role of the microbiome metabolism of this xenobiotic and the impact on host responses is unclear. We exposed successive generations of the wasp Nasonia vitripennis to subtoxic levels of atrazine and observed changes in the structure and function of the gut microbiome that conveyed atrazine resistance. This microbiome-mediated resistance was maternally inherited and increased over successive generations, while also heightening the rate of host genome selection. The rare gut bacteria Serratia marcescens and Pseudomonas protegens contributed to atrazine metabolism. Both of these bacteria contain genes that are linked to atrazine degradation and were sufficient to confer resistance in experimental wasp populations. Thus, pesticide exposure causes functional, inherited changes in the microbiome that should be considered when assessing xenobiotic exposure and as potential countermeasures to toxicity. | 2020 | 32023487 |
| 8810 | 14 | 0.9802 | Mechanisms involved in the sequestration and resistance of cadmium for a plant-associated Pseudomonas strain. Understanding Cd-resistant bacterial cadmium (Cd) resistance systems is crucial for improving microremediation in Cd-contaminated environments. However, these mechanisms are not fully understood in plant-associated bacteria. In the present study, we investigated the mechanisms underlying Cd sequestration and resistance in the strain AN-B15. These results showed that extracellular Cd sequestration by complexation in strain AN-B15 was primarily responsible for the removal of Cd from the solution. Transcriptome analyses have shown that the mechanisms of Cd resistance at the transcriptional level involve collaborative processes involving multiple metabolic pathways. The AN-B15 strain upregulated the expression of genes related to exopolymeric substance synthesis, metal transport, Fe-S cluster biogenesis, iron recruitment, reactive oxygen species oxidative stress defense, and DNA and protein repair to resist Cd-induced stress. Furthermore, inoculation with AN-B15 alleviated Cd-induced toxicity and reduced Cd uptake in the shoots of wheat seedlings, indicating its potential for remediation. Overall, the results improve our understanding of the mechanisms involved in Cd resistance in bacteria and thus have important implications for improving microremediation. | 2023 | 37806135 |
| 508 | 15 | 0.9802 | Insights into the chaotropic tolerance of the desert cyanobacterium Chroococcidiopsis sp. 029 (Chroococcidiopsales, Cyanobacteria). The mechanism of perchlorate resistance of the desert cyanobacterium Chroococcidiopsis sp. CCMEE 029 was investigated by assessing whether the pathways associated with its desiccation tolerance might play a role against the destabilizing effects of this chaotropic agent. During 3 weeks of growth in the presence of 2.4 mM perchlorate, an upregulation of trehalose and sucrose biosynthetic pathways was detected. This suggested that in response to the water stress triggered by perchlorate salts, these two compatible solutes play a role in the stabilization of macromolecules and membranes as they do in response to dehydration. During the perchlorate exposure, the production of oxidizing species was observed by using an oxidant-sensing fluorochrome and determining the expression of the antioxidant defense genes, namely superoxide dismutases and catalases, while the presence of oxidative DNA damage was highlighted by the over-expression of genes of the base excision repair. The involvement of desiccation-tolerance mechanisms in the perchlorate resistance of this desert cyanobacterium is interesting since, so far, chaotropic-tolerant bacteria have been identified among halophiles. Hence, it is anticipated that desert microorganisms might possess an unrevealed capability of adapting to perchlorate concentrations exceeding those naturally occurring in dry environments. Furthermore, in the endeavor of supporting future human outposts on Mars, the identified mechanisms might contribute to enhance the perchlorate resistance of microorganisms relevant for biologically driven utilization of the perchlorate-rich soil of the red planet. | 2024 | 38156502 |
| 653 | 16 | 0.9801 | Connecting Algal Polysaccharide Degradation to Formaldehyde Detoxification. Formaldehyde is a toxic metabolite that is formed in large quantities during bacterial utilization of the methoxy sugar 6-O-methyl-d-galactose, an abundant monosaccharide in the red algal polysaccharide porphyran. Marine bacteria capable of metabolizing porphyran must therefore possess suitable detoxification systems for formaldehyde. We demonstrate here that detoxification of formaldehyde in the marine Flavobacterium Zobellia galactanivorans proceeds via the ribulose monophosphate pathway. Simultaneously, we show that the genes encoding the key enzymes of this pathway are important for maintaining high formaldehyde resistance. Additionally, these genes are upregulated in the presence of porphyran, allowing us to connect porphyran degradation to the detoxification of formed formaldehyde. | 2022 | 35561127 |
| 8643 | 17 | 0.9801 | Diversity of Phototrophic Genes Suggests Multiple Bacteria May Be Able to Exploit Sunlight in Exposed Soils from the Sør Rondane Mountains, East Antarctica. Microbial life in exposed terrestrial surface layers in continental Antarctica is faced with extreme environmental conditions, including scarcity of organic matter. Bacteria in these exposed settings can therefore be expected to use alternative energy sources such as solar energy, abundant during the austral summer. Using Illumina MiSeq sequencing, we assessed the diversity and abundance of four conserved protein encoding genes involved in different key steps of light-harvesting pathways dependent on (bacterio)chlorophyll (pufM, bchL/chlL, and bchX genes) and rhodopsins (actinorhodopsin genes), in exposed soils from the Sør Rondane Mountains, East Antarctica. Analysis of pufM genes, encoding a subunit of the type 2 photochemical reaction center found in anoxygenic phototrophic bacteria, revealed a broad diversity, dominated by Roseobacter- and Loktanella-like sequences. The bchL and chlL, involved in (bacterio)chlorophyll synthesis, on the other hand, showed a high relative abundance of either cyanobacterial or green algal trebouxiophyceael chlL reads, depending on the sample, while most bchX sequences belonged mostly to previously unidentified phylotypes. Rhodopsin-containing phototrophic bacteria could not be detected in the samples. Our results, while suggesting that Cyanobacteria and green algae are the main phototrophic groups, show that light-harvesting bacteria are nevertheless very diverse in microbial communities in Antarctic soils. | 2016 | 28066352 |
| 8544 | 18 | 0.9801 | Closed fixed-bed bacteria-algae biofilm reactor: A promising solution for phenol containing wastewater treatment and resource transformation. This study focuses on treating phenolic wastewater with a novel closed fixed-bed bacteria-algae biofilm reactor (CF-BABR) to enhance resource transformation for phenolic substances. The CF-BABR showed strong impact - load resistance and stable degradation efficiency, fully degrading phenolic compounds at concentrations from 0 to 150 mg/L. From the inflow to the outflow, the effective sequences, abundance, and diversity of bacteria decreased. Chlorobaculum was the dominant bacterium for phenolic pollutant degradation. The abundance of fungi decreased gradually, while their diversity increased. Kalenjinia and Cutaneotrichosporon played a synergistic role in reducing pollutant toxicity. The high - concentration pollutants at the influent led to a higher abundance of microalgal communities, and Scenedesmaceae became the most dominant algal family, which was positively correlated with the degradation of phenolic compounds. Functional gene prediction indicated that the abundance of functional genes in bacteria decreased overall along the wastewater flow. Carbohydrate metabolism and amino acid metabolism were the most active secondary pathways. In fungi, the predicted gene functions had the highest abundance in the upstream region. Metabolic intermediates such as organic acids and derivatives, lipids and lipid - like molecules, and carboxylic acids and derivatives demonstrated the degradation effect of CF-BABR on phenolic compounds. | 2025 | 40194331 |
| 580 | 19 | 0.9801 | Acid-tolerant bacteria and prospects in industrial and environmental applications. Acid-tolerant bacteria such as Streptococcus mutans, Acidobacterium capsulatum, Escherichia coli, and Propionibacterium acidipropionici have developed several survival mechanisms to sustain themselves in various acid stress conditions. Some bacteria survive by minor changes in the environmental pH. In contrast, few others adapt different acid tolerance mechanisms, including amino acid decarboxylase acid resistance systems, mainly glutamate-dependent acid resistance (GDAR) and arginine-dependent acid resistance (ADAR) systems. The cellular mechanisms of acid tolerance include cell membrane alteration in Acidithiobacillus thioxidans, proton elimination by F(1)-F(0)-ATPase in Streptococcus pyogenes, biofilm formation in Pseudomonas aeruginosa, cytoplasmic urease activity in Streptococcus mutans, synthesis of the protective cloud of ammonia, and protection or repair of macromolecules in Bacillus caldontenax. Apart from cellular mechanisms, there are several acid-tolerant genes such as gadA, gadB, adiA, adiC, cadA, cadB, cadC, speF, and potE that help the bacteria to tolerate the acidic environment. This acid tolerance behavior provides new and broad prospects for different industrial applications and the bioremediation of environmental pollutants. The development of engineered strains with acid-tolerant genes may improve the efficiency of the transgenic bacteria in the treatment of acidic industrial effluents. KEY POINTS: • Bacteria tolerate the acidic stress by methylating unsaturated phospholipid tail • The activity of decarboxylase systems for acid tolerance depends on pH • Genetic manipulation of acid-tolerant genes improves acid tolerance by the bacteria. | 2023 | 37093306 |