The electrically conductive pili of Geobacter species are a recently evolved feature for extracellular electron transfer

Microbial Genomics, Journal Year: 2016, Volume and Issue: 2(8)

Published: June 6, 2016

The electrically conductive pili (e-pili) of Geobactersulfurreducens have environmental and practical significance because they can facilitate electron transfer to insoluble Fe(III) oxides; other microbial species; through biofilms. E-pili conductivity has been attributed the truncated PilA monomer, which permits tight packing aromatic amino acids form a path along length e-pili. In order better understand evolution distribution e-pili in world, type IVa proteins from various Gram-negative Gram-positive bacteria were examined with particular emphasis on Fe(III)-respiring bacteria. E-pilin genes are primarily restricted phylogenetic group Desulfuromonadales. downstream gene all but one Desulfuromonadales that possess an e-pilin is previously annotated as ‘ pilA–C ’ characteristics suggesting it may encode outer-membrane protein. Other associated pilin function clustered contrast, few outside contain genes, required for acquired horizontal transfer. Of 95 known Fe(III)-reducing micro-organisms genomes available, 80 % lack just several mechanisms involved extracellular transport. These studies provide insight into where when likely contribute transport processes biogeochemically important bioenergy conversions.

Language: Английский

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A Phylogenomic Analysis of the Bacterial Phylum Fibrobacteres

Frontiers in Microbiology, Journal Year: 2016, Volume and Issue: 6

Published: Jan. 7, 2016

The Fibrobacteres has been recognized as a bacterial phylum for over decade, but little is known about the group beyond its environmental distribution, and characterization of sole cultured representative genus, Fibrobacter, after which was named. Based on these incomplete data, it thought that cellulose hydrolysis, anaerobic metabolism, lack motility are unifying features phylum. There also contradicting views to whether an uncultured sister lineage, candidate TG3, should be included in Fibrobacteres. Recently, chitin-degrading representatives TG3 were isolated from hypersaline soda lake, genome one species, Chitinivibrio alkaliphilus, sequenced described detail. Here, we performed comparative analysis Fibrobacter succinogenes, C. alkaliphilus eight near or substantially complete Fibrobacteres/TG3 genomes populations recovered termite gut, digester, sheep rumen metagenomes. We propose amalgamated with based robust monophyly two lineages shared character traits. Polymer using distinctive set glycoside hydrolases binding domains, appears prominent feature members Not all this strictly some gut have respiratory chains adapted microaerophilic conditions found habitat. Contrary expectations, flagella-based predicted ancestral common trait only recently lost F. succinogenes relatives phylogenetic distribution flagellar genes. Our findings extend current understanding provide improved basis further investigation

Language: Английский

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Nanomaterials Facilitating Microbial Extracellular Electron Transfer at Interfaces

Advanced Materials, Journal Year: 2020, Volume and Issue: 33(6)

Published: Dec. 16, 2020

Abstract Electrochemically active bacteria can transport their metabolically generated electrons to anodes, or accept from cathodes synthesize high‐value chemicals and fuels, via a process known as extracellular electron transfer (EET). Harnessing of this microbial EET has led the development bio‐electrochemical systems (BESs), which achieve interconversion electrical chemical energy enable electricity generation, hydrogen production, electrosynthesis, wastewater treatment, desalination, water soil remediation, sensing. Here, focus is on current understanding occurring at both bacteria–electrode interface biotic interface, well some attempts improve by using various nanomaterials. The behavior nanomaterials in different routes influence performance BESs are described. inherent mechanisms will guide rational design EET‐related materials lead better mechanisms.

Language: Английский

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Cyclic Di-GMP Riboswitch-Regulated Type IV Pili Contribute to Aggregation of Clostridium difficile

Journal of Bacteriology, Journal Year: 2014, Volume and Issue: 197(5), P. 819 - 832

Published: Dec. 16, 2014

ABSTRACT Clostridium difficile is an anaerobic Gram-positive bacterium that causes intestinal infections with symptoms ranging from mild diarrhea to fulminant colitis. Cyclic diguanosine monophosphate (c-di-GMP) a bacterial second messenger typically regulates the switch motile, free-living sessile and multicellular behaviors in Gram-negative bacteria. Increased intracellular c-di-GMP concentration C. was recently shown reduce flagellar motility increase cell aggregation. In this work, we investigated role of primary type IV pilus (T4P) locus c-di-GMP-dependent Inactivation two T4P genes, pilA1 (CD3513) pilB1 (CD3512), abolished formation significantly reduced aggregation under high conditions. preceded by putative riboswitch, predicted be transcriptionally active upon binding. Consistent our prediction, increased transcript levels genes. addition, single-round vitro transcription assays confirmed downstream terminator dose dependent specific binding riboswitch aptamer. These results support model which gene upregulated as result its upstream activating promoting .

Language: Английский

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The distinction of CPR bacteria from other bacteria based on protein family content

Nature Communications, Journal Year: 2019, Volume and Issue: 10(1)

Published: Sept. 13, 2019

Abstract Candidate phyla radiation (CPR) bacteria separate phylogenetically from other bacteria, but the organismal distribution of their protein families remains unclear. Here, we leveraged sequences thousands uncultivated organisms and identified that co-occur in genomes, thus are likely foundational for lineage capacities. Protein family presence/absence patterns cluster CPR together, away all archaea, partly due to proteins without recognizable homology bacteria. Some involved cell-cell interactions potentially important episymbiotic lifestyles. The diversity combinations may exceed Over bacterial tree, broadly recapitulate phylogenetic structure, suggesting persistence core sets since divergence. could have arisen an episode dramatic heterogeneous genome reduction or a protogenote community co-evolved with

Language: Английский

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