1
|
Premachandre CK, Vaz PK, Sharma S, Kanci Condello A, Browning GF, Wawegama NK. Genes required for survival and proliferation of Mycoplasma bovis in association with host cells. Appl Environ Microbiol 2024; 90:e0068724. [PMID: 38864628 PMCID: PMC11267936 DOI: 10.1128/aem.00687-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Accepted: 05/19/2024] [Indexed: 06/13/2024] Open
Abstract
Mycoplasma bovis is an important emerging pathogen of cattle and bison, but our understanding of the genetic basis of its interactions with its host is limited. The aim of this study was to identify genes of M. bovis required for interaction and survival in association with host cells. One hundred transposon-induced mutants of the type strain PG45 were assessed for their capacity to survive and proliferate in Madin-Darby bovine kidney cell cultures. The growth of 19 mutants was completely abrogated, and 47 mutants had a prolonged doubling time compared to the parent strain. All these mutants had a similar growth pattern to the parent strain PG45 in the axenic media. Thirteen genes previously classified as dispensable for the axenic growth of M. bovis were found to be essential for the growth of M. bovis in association with host cells. In most of the mutants with a growth-deficient phenotype, the transposon was inserted into a gene involved in transportation or metabolism. This included genes coding for ABC transporters, proteins related to carbohydrate, nucleotide and protein metabolism, and membrane proteins essential for attachment. It is likely that these genes are essential not only in vitro but also for the survival of M. bovis in infected animals. IMPORTANCE Mycoplasma bovis causes chronic bronchopneumonia, mastitis, arthritis, keratoconjunctivitis, and reproductive tract disease in cattle around the globe and is an emerging pathogen in bison. Control of mycoplasma infections is difficult in the absence of appropriate antimicrobial treatment or effective vaccines. A comprehensive understanding of host-pathogen interactions and virulence factors is important to implement more effective control methods against M. bovis. Recent studies of other mycoplasmas with in vitro cell culture models have identified essential virulence genes of mycoplasmas. Our study has identified genes of M. bovis required for survival in association with host cells, which will pave the way to a better understanding of host-pathogen interactions and the role of specific genes in the pathogenesis of disease caused by M. bovis.
Collapse
Affiliation(s)
- Chintha K. Premachandre
- Asia-Pacific Center for Animal Health, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria, Australia
| | - Paola K. Vaz
- Asia-Pacific Center for Animal Health, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria, Australia
| | - Shukriti Sharma
- Asia-Pacific Center for Animal Health, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria, Australia
| | - Anna Kanci Condello
- Asia-Pacific Center for Animal Health, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria, Australia
| | - Glenn F. Browning
- Asia-Pacific Center for Animal Health, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria, Australia
| | - Nadeeka K. Wawegama
- Asia-Pacific Center for Animal Health, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria, Australia
| |
Collapse
|
2
|
A Mycoplasma gallisepticum Glycerol ABC Transporter Involved in Pathogenicity. Appl Environ Microbiol 2021; 87:AEM.03112-20. [PMID: 33741628 DOI: 10.1128/aem.03112-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Accepted: 03/02/2021] [Indexed: 11/20/2022] Open
Abstract
MalF has been shown to be required for virulence in the important avian pathogen Mycoplasma gallisepticum To characterize the function of MalF, predicted to be part of a putative ABC transporter, we compared metabolite profiles of a mutant with a transposon inserted in malF (MalF-deficient ST mutant 04-1; ΔmalF) with those of wild-type bacteria using gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry. Of the substrates likely to be transported by an ABC transport system, glycerol was detected at significantly lower abundance in the ΔmalF mutant, compared to the wild type. Stable isotope labeling using [U-13C]glycerol and reverse transcription-quantitative PCR analysis indicated that MalF was responsible for the import of glycerol into M. gallisepticum and that, in the absence of MalF, the transcription of gtsA, which encodes a second transporter, GtsA, was upregulated, potentially to increase the import of glycerol-3-phosphate into the cell to compensate for the loss of MalF. The loss of MalF appeared to have a global effect on glycerol metabolism, suggesting that it may also play a regulatory role, and cellular morphology was also affected, indicating that the change to glycerol metabolism may have a broader effect on cellular organization. Overall, this study suggests that the reduced virulence of the ΔmalF mutant is due to perturbed glycerol uptake and metabolism and that the operon including malF should be reannotated as golABC to reflect its function in glycerol transport.IMPORTANCE Many mycoplasmas are pathogenic and cause disease in humans and animals. M. gallisepticum causes chronic respiratory disease in chickens and infectious sinusitis in turkeys, resulting in economic losses in poultry industries throughout the world. Expanding our knowledge about the pathogenesis of mycoplasma infections requires better understanding of the specific gene functions of these bacteria. In this study, we have characterized the metabolic function of a protein involved in the pathogenicity of M. gallisepticum, as well as its effect on expression of selected genes, cell phenotype, and H2O2 production. This study is a key step forward in elucidating why this protein plays a key role in virulence in chickens. This study also emphasizes the importance of functional characterization of mycoplasma proteins, using tools such as metabolomics, since prediction of function based on homology to other bacterial proteins is not always accurate.
Collapse
|
3
|
Felestrino ÉB, Sanchez AB, Caneschi WL, Lemes CGDC, Assis RDAB, Cordeiro IF, Fonseca NP, Villa MM, Vieira IT, Kamino LHY, do Carmo FF, da Silva AM, Thomas AM, Patané JSL, Ferreira FC, de Freitas LG, Varani ADM, Ferro JA, Silva RS, Almeida NF, Garcia CCM, Setubal JC, Moreira LM. Complete genome sequence and analysis of Alcaligenes faecalis strain Mc250, a new potential plant bioinoculant. PLoS One 2020; 15:e0241546. [PMID: 33151992 PMCID: PMC7643998 DOI: 10.1371/journal.pone.0241546] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 10/16/2020] [Indexed: 11/19/2022] Open
Abstract
Here we present and analyze the complete genome of Alcaligenes faecalis strain Mc250 (Mc250), a bacterium isolated from the roots of Mimosa calodendron, an endemic plant growing in ferruginous rupestrian grasslands in Minas Gerais State, Brazil. The genome has 4,159,911 bp and 3,719 predicted protein-coding genes, in a single chromosome. Comparison of the Mc250 genome with 36 other Alcaligenes faecalis genomes revealed that there is considerable gene content variation among these strains, with the core genome representing only 39% of the protein-coding gene repertoire of Mc250. Mc250 encodes a complete denitrification pathway, a network of pathways associated with phenolic compounds degradation, and genes associated with HCN and siderophores synthesis; we also found a repertoire of genes associated with metal internalization and metabolism, sulfate/sulfonate and cysteine metabolism, oxidative stress and DNA repair. These findings reveal the genomic basis for the adaptation of this bacterium to the harsh environmental conditions from where it was isolated. Gene clusters associated with ectoine, terpene, resorcinol, and emulsan biosynthesis that can confer some competitive advantage were also found. Experimental results showed that Mc250 was able to reduce (~60%) the virulence phenotype of the plant pathogen Xanthomonas citri subsp. citri when co-inoculated in Citrus sinensis, and was able to eradicate 98% of juveniles and stabilize the hatching rate of eggs to 4% in two species of agricultural nematodes. These results reveal biotechnological potential for the Mc250 strain and warrant its further investigation as a biocontrol and plant growth-promoting bacterium.
Collapse
Affiliation(s)
- Érica Barbosa Felestrino
- Núcleo de Pesquisas em Ciências Biológicas (NUPEB), Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
| | - Angélica Bianchini Sanchez
- Núcleo de Pesquisas em Ciências Biológicas (NUPEB), Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
| | - Washington Luiz Caneschi
- Núcleo de Pesquisas em Ciências Biológicas (NUPEB), Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
| | | | | | - Isabella Ferreira Cordeiro
- Núcleo de Pesquisas em Ciências Biológicas (NUPEB), Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
| | - Natasha Peixoto Fonseca
- Núcleo de Pesquisas em Ciências Biológicas (NUPEB), Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
| | - Morghana Marina Villa
- Departamento de Ciências Biológicas (DECBI), Instituto de Ciências Exatas e Biológicas (ICEB), Universidade Federal de Ouro Preto (UFOP), Ouro Preto, MG, Brazil
| | - Izadora Tabuso Vieira
- Departamento de Ciências Biológicas (DECBI), Instituto de Ciências Exatas e Biológicas (ICEB), Universidade Federal de Ouro Preto (UFOP), Ouro Preto, MG, Brazil
| | | | | | - Aline Maria da Silva
- Departamento de Bioquímica (DBQ), Instituto de Química (IQ), Universidade de São Paulo (USP), São Paulo, SP, Brazil
| | - Andrew Maltez Thomas
- Departamento de Bioquímica (DBQ), Instituto de Química (IQ), Universidade de São Paulo (USP), São Paulo, SP, Brazil
| | | | - Fernanda Carla Ferreira
- Instituto de Biotecnologia Aplicada a Agropecuária (BIOAGRO), Universidade Federal de Viçosa (UFV), Viçosa, MG, Brazil
| | - Leandro Grassi de Freitas
- Instituto de Biotecnologia Aplicada a Agropecuária (BIOAGRO), Universidade Federal de Viçosa (UFV), Viçosa, MG, Brazil
| | - Alessandro de Mello Varani
- Departamento de Tecnologia, Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal (FCAV), Universidade Estadual Paulista (UNESP), São Paulo, SP, Brazil
| | - Jesus Aparecido Ferro
- Departamento de Tecnologia, Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal (FCAV), Universidade Estadual Paulista (UNESP), São Paulo, SP, Brazil
| | - Robson Soares Silva
- Faculdade de Computação (FACOM), Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil
| | - Nalvo Franco Almeida
- Faculdade de Computação (FACOM), Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil
| | - Camila Carrião Machado Garcia
- Núcleo de Pesquisas em Ciências Biológicas (NUPEB), Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
- Departamento de Ciências Biológicas (DECBI), Instituto de Ciências Exatas e Biológicas (ICEB), Universidade Federal de Ouro Preto (UFOP), Ouro Preto, MG, Brazil
| | - João Carlos Setubal
- Departamento de Bioquímica (DBQ), Instituto de Química (IQ), Universidade de São Paulo (USP), São Paulo, SP, Brazil
- * E-mail: (JCS); (LMM)
| | - Leandro Marcio Moreira
- Núcleo de Pesquisas em Ciências Biológicas (NUPEB), Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
- Departamento de Ciências Biológicas (DECBI), Instituto de Ciências Exatas e Biológicas (ICEB), Universidade Federal de Ouro Preto (UFOP), Ouro Preto, MG, Brazil
- * E-mail: (JCS); (LMM)
| |
Collapse
|
4
|
Chandravanshi M, Gogoi P, Kanaujia SP. Computational characterization of TTHA0379: A potential glycerophosphocholine binding protein of Ugp ATP-binding cassette transporter. Gene 2016; 592:260-8. [DOI: 10.1016/j.gene.2016.07.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 07/04/2016] [Accepted: 07/05/2016] [Indexed: 11/16/2022]
|
5
|
Abstract
Mycobacteria inhabit a wide range of intracellular and extracellular environments. Many of these environments are highly dynamic and therefore mycobacteria are faced with the constant challenge of redirecting their metabolic activity to be commensurate with either replicative growth or a non-replicative quiescence. A fundamental feature in this adaptation is the ability of mycobacteria to respire, regenerate reducing equivalents and generate ATP via oxidative phosphorylation. Mycobacteria harbor multiple primary dehydrogenases to fuel the electron transport chain and two terminal respiratory oxidases, an aa3 -type cytochrome c oxidase and cytochrome bd-type menaquinol oxidase, are present for dioxygen reduction coupled to the generation of a protonmotive force. Hypoxia leads to the downregulation of key respiratory complexes, but the molecular mechanisms regulating this expression are unknown. Despite being obligate aerobes, mycobacteria have the ability to metabolize in the absence of oxygen and a number of reductases are present to facilitate the turnover of reducing equivalents under these conditions (e.g. nitrate reductase, succinate dehydrogenase/fumarate reductase). Hydrogenases and ferredoxins are also present in the genomes of mycobacteria suggesting the ability of these bacteria to adapt to an anaerobic-type of metabolism in the absence of oxygen. ATP synthesis by the membrane-bound F1FO-ATP synthase is essential for growing and non-growing mycobacteria and the enzyme is able to function over a wide range of protonmotive force values (aerobic to hypoxic). The discovery of lead compounds that target respiration and oxidative phosphorylation in Mycobacterium tuberculosis highlights the importance of this area for the generation of new front line drugs to combat tuberculosis.
Collapse
|
6
|
Stopnisek N, Zühlke D, Carlier A, Barberán A, Fierer N, Becher D, Riedel K, Eberl L, Weisskopf L. Molecular mechanisms underlying the close association between soil Burkholderia and fungi. ISME JOURNAL 2015; 10:253-64. [PMID: 25989372 DOI: 10.1038/ismej.2015.73] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 03/24/2015] [Accepted: 03/26/2015] [Indexed: 01/27/2023]
Abstract
Bacterial species belonging to the genus Burkholderia have been repeatedly reported to be associated with fungi but the extent and specificity of these associations in soils remain undetermined. To assess whether associations between Burkholderia and fungi are widespread in soils, we performed a co-occurrence analysis in an intercontinental soil sample collection. This revealed that Burkholderia significantly co-occurred with a wide range of fungi. To analyse the molecular basis of the interaction, we selected two model fungi frequently co-occurring with Burkholderia, Alternaria alternata and Fusarium solani, and analysed the proteome changes caused by cultivation with either fungus in the widespread soil inhabitant B. glathei, whose genome we sequenced. Co-cultivation with both fungi led to very similar changes in the B. glathei proteome. Our results indicate that B. glathei significantly benefits from the interaction, which is exemplified by a lower abundance of several starvation factors that were highly expressed in pure culture. However, co-cultivation also gave rise to stress factors, as indicated by the increased expression of multidrug efflux pumps and proteins involved in oxidative stress response. Our data suggest that the ability of Burkholderia to establish a close association with fungi mainly lies in the capacities to utilize fungal-secreted metabolites and to overcome fungal defense mechanisms. This work indicates that beneficial interactions with fungi might contribute to the survival strategy of Burkholderia species in environments with sub-optimal conditions, including acidic soils.
Collapse
Affiliation(s)
- Nejc Stopnisek
- Institute of Plant Biology, University of Zurich, Zürich, Switzerland.,Institute for Sustainability Sciences, Agroscope, Zürich, Switzerland
| | - Daniela Zühlke
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Aurélien Carlier
- Institute of Plant Biology, University of Zurich, Zürich, Switzerland
| | - Albert Barberán
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - Noah Fierer
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA.,Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA
| | - Dörte Becher
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Katharina Riedel
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Leo Eberl
- Institute of Plant Biology, University of Zurich, Zürich, Switzerland
| | - Laure Weisskopf
- Institute of Plant Biology, University of Zurich, Zürich, Switzerland.,Institute for Sustainability Sciences, Agroscope, Zürich, Switzerland
| |
Collapse
|
7
|
Vetting MW, Al-Obaidi N, Zhao S, San Francisco B, Kim J, Wichelecki DJ, Bouvier JT, Solbiati JO, Vu H, Zhang X, Rodionov DA, Love JD, Hillerich BS, Seidel RD, Quinn RJ, Osterman AL, Cronan JE, Jacobson MP, Gerlt JA, Almo SC. Experimental strategies for functional annotation and metabolism discovery: targeted screening of solute binding proteins and unbiased panning of metabolomes. Biochemistry 2015; 54:909-31. [PMID: 25540822 PMCID: PMC4310620 DOI: 10.1021/bi501388y] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
![]()
The
rate at which genome sequencing data is accruing demands enhanced
methods for functional annotation and metabolism discovery. Solute
binding proteins (SBPs) facilitate the transport of the first reactant
in a metabolic pathway, thereby constraining the regions of chemical
space and the chemistries that must be considered for pathway reconstruction.
We describe high-throughput protein production and differential scanning
fluorimetry platforms, which enabled the screening of 158 SBPs against
a 189 component library specifically tailored for this class of proteins.
Like all screening efforts, this approach is limited by the practical
constraints imposed by construction of the library, i.e., we can study
only those metabolites that are known to exist and which can be made
in sufficient quantities for experimentation. To move beyond these
inherent limitations, we illustrate the promise of crystallographic-
and mass spectrometric-based approaches for the unbiased use of entire
metabolomes as screening libraries. Together, our approaches identified
40 new SBP ligands, generated experiment-based annotations for 2084
SBPs in 71 isofunctional clusters, and defined numerous metabolic
pathways, including novel catabolic pathways for the utilization of
ethanolamine as sole nitrogen source and the use of d-Ala-d-Ala as sole carbon source. These efforts begin to define an
integrated strategy for realizing the full value of amassing genome
sequence data.
Collapse
Affiliation(s)
- Matthew W Vetting
- Department of Biochemistry, Albert Einstein College of Medicine , Bronx, New York 10461, United States
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Basu A, Mishra B, Leong SSJ. Global transcriptome analysis reveals distinct bacterial response towards soluble and surface-immobilized antimicrobial peptide (Lasioglossin-III). RSC Adv 2015. [DOI: 10.1039/c5ra14862f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Bacterial response towards soluble and immobilized AMP molecules revealed through global transcriptome analysis.
Collapse
Affiliation(s)
- Anindya Basu
- School of Chemical and Biomedical Engineering
- Nanyang Technological University
- Singapore 637459
| | - Biswajit Mishra
- School of Chemical and Biomedical Engineering
- Nanyang Technological University
- Singapore 637459
| | - Susanna Su Jan Leong
- Singapore Institute of Technology
- Singapore 138683
- Department of Biochemistry
- Yong Loo Lin School of Medicine
- National University of Singapore
| |
Collapse
|
9
|
Bayer K, Moitinho-Silva L, Brümmer F, Cannistraci CV, Ravasi T, Hentschel U. GeoChip-based insights into the microbial functional gene repertoire of marine sponges (high microbial abundance, low microbial abundance) and seawater. FEMS Microbiol Ecol 2014; 90:832-43. [PMID: 25318900 DOI: 10.1111/1574-6941.12441] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 09/30/2014] [Accepted: 10/06/2014] [Indexed: 12/12/2022] Open
Abstract
The GeoChip 4.2 gene array was employed to interrogate the microbial functional gene repertoire of sponges and seawater collected from the Red Sea and the Mediterranean. Complementary amplicon sequencing confirmed the microbial community composition characteristic of high microbial abundance (HMA) and low microbial abundance (LMA) sponges. By use of GeoChip, altogether 20,273 probes encoding for 627 functional genes and representing 16 gene categories were identified. Minimum curvilinear embedding analyses revealed a clear separation between the samples. The HMA/LMA dichotomy was stronger than any possible geographic pattern, which is shown here for the first time on the level of functional genes. However, upon inspection of individual genes, very few specific differences were discernible. Differences were related to microbial ammonia oxidation, ammonification, and archaeal autotrophic carbon fixation (higher gene abundance in sponges over seawater) as well as denitrification and radiation-stress-related genes (lower gene abundance in sponges over seawater). Except for few documented specific differences the functional gene repertoire between the different sources appeared largely similar. This study expands previous reports in that functional gene convergence is not only reported between HMA and LMA sponges but also between sponges and seawater.
Collapse
Affiliation(s)
- Kristina Bayer
- Department of Botany II, Julius-von-Sachs Institute for Biological Sciences, University of Wuerzburg, Wuerzburg, Germany
| | | | | | | | | | | |
Collapse
|
10
|
Berney M, Cook GM. Respiration and Oxidative Phosphorylation in Mycobacteria. THE STRUCTURAL BASIS OF BIOLOGICAL ENERGY GENERATION 2014. [DOI: 10.1007/978-94-017-8742-0_15] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
|
11
|
Wuttge S, Bommer M, Jäger F, Martins BM, Jacob S, Licht A, Scheffel F, Dobbek H, Schneider E. Determinants of substrate specificity and biochemical properties of the sn-glycerol-3-phosphate ATP binding cassette transporter (UgpB-AEC2 ) of Escherichia coli. Mol Microbiol 2012; 86:908-20. [PMID: 23013274 DOI: 10.1111/mmi.12025] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/30/2012] [Indexed: 12/20/2022]
Abstract
Under phosphate starvation conditions, Escherichia coli can utilize sn-glycerol-3-phosphate (G3P) and G3P diesters as phosphate source when transported by an ATP binding cassette importer composed of the periplasmic binding protein, UgpB, the transmembrane subunits, UgpA and UgpE, and a homodimer of the nucleotide binding subunit, UgpC. The current knowledge on the Ugp transporter is solely based on genetic evidence and transport assays using intact cells. Thus, we set out to characterize its properties at the level of purified protein components. UgpB was demonstrated to bind G3P and glycerophosphocholine with dissociation constants of 0.68 ± 0.02 μM and 5.1 ± 0.3 μM, respectively, while glycerol-2-phosphate (G2P) is not a substrate. The crystal structure of UgpB in complex with G3P was solved at 1.8 Å resolution and revealed the interaction with two tryptophan residues as key to the preferential binding of linear G3P in contrast to the branched G2P. Mutational analysis validated the crucial role of Trp-169 for G3P binding. The purified UgpAEC2 complex displayed UgpB/G3P-stimulated ATPase activity in proteoliposomes that was neither inhibited by phosphate nor by the signal transducing protein PhoU or the phosphodiesterase UgpQ. Furthermore, a hybrid transporter composed of MalFG-UgpC could be functionally reconstituted while a UgpAE-MalK complex was unstable.
Collapse
Affiliation(s)
- Steven Wuttge
- Division of Microbial Physiology, Humboldt-Universität zu Berlin, Unter den Linden 6, D-10099, Berlin, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Abstract
Sponges harbour complex communities of diverse microorganisms, which have been postulated to form intimate symbiotic relationships with their host. Here we unravel some of these interactions by characterising the functional features of the microbial community of the sponge Cymbastela concentrica through a combined metagenomic and metaproteomic approach. We discover the expression of specific transport functions for typical sponge metabolites (for example, halogenated aromatics, dipeptides), which indicates metabolic interactions between the community and the host. We also uncover the simultaneous performance of aerobic nitrification and anaerobic denitrification, which would aid to remove ammonium secreted by the sponge. Our analysis also highlights the requirement for the microbial community to respond to variable environmental conditions and hence express an array of stress protection proteins. Molecular interactions between symbionts and their host might also be mediated by a set of expressed eukaryotic-like proteins and cell-cell mediators. Finally, some sponge-associated bacteria (for example, a Phyllobacteriaceae phylotype) appear to undergo an evolutionary adaptation process to the sponge environment as evidenced by active mobile genetic elements. Our data clearly show that a combined metaproteogenomic approach can provide novel information on the activities, physiology and interactions of sponge-associated microbial communities.
Collapse
|
13
|
Interaction of fosfomycin with the Glycerol 3-phosphate Transporter of Escherichia coli. Biochim Biophys Acta Gen Subj 2011; 1810:1323-9. [DOI: 10.1016/j.bbagen.2011.07.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2011] [Revised: 07/11/2011] [Accepted: 07/12/2011] [Indexed: 11/23/2022]
|
14
|
Crépin S, Lamarche MG, Garneau P, Séguin J, Proulx J, Dozois CM, Harel J. Genome-wide transcriptional response of an avian pathogenic Escherichia coli (APEC) pst mutant. BMC Genomics 2008; 9:568. [PMID: 19038054 PMCID: PMC2648988 DOI: 10.1186/1471-2164-9-568] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2008] [Accepted: 11/28/2008] [Indexed: 11/20/2022] Open
Abstract
Background Avian pathogenic E. coli (APEC) are associated with extraintestinal diseases in poultry. The pstSCAB-phoU operon belongs to the Pho regulon and encodes the phosphate specific transport (Pst) system. A functional Pst system is required for full virulence in APEC and other bacteria and contributes to resistance of APEC to serum, to cationic antimicrobial peptides and acid shock. The global mechanisms contributing to the attenuation and decreased resistance of the APEC pst mutant to environmental stresses have not been investigated at the transcriptional level. To determine the global effect of a pst mutation on gene expression, we compared the transcriptomes of APEC strain χ7122 and its isogenic pst mutant (K3) grown in phosphate-rich medium. Results Overall, 470 genes were differentially expressed by at least 1.5-fold. Interestingly, the pst mutant not only induced systems involved in phosphate acquisition and metabolism, despite phosphate availability, but also modulated stress response mechanisms. Indeed, transcriptional changes in genes associated with the general stress responses, including the oxidative stress response were among the major differences observed. Accordingly, the K3 strain was less resistant to reactive oxygen species (ROS) than the wild-type strain. In addition, the pst mutant demonstrated reduced expression of genes involved in lipopolysaccharide modifications and coding for cell surface components such as type 1 and F9 fimbriae. Phenotypic tests also established that the pst mutant was impaired in its capacity to produce type 1 fimbriae, as demonstrated by western blotting and agglutination of yeast cells, when compared to wild-type APEC strain χ7122. Conclusion Overall, our data elucidated the effects of a pst mutation on the transcriptional response, and further support the role of the Pho regulon as part of a complex network contributing to phosphate homeostasis, adaptive stress responses, and E. coli virulence.
Collapse
Affiliation(s)
- Sébastien Crépin
- Groupe de Recherche sur les Maladies Infectieuses du Porc (GREMIP), Université de Montréal, Faculté de Médecine Vétérinaire, Saint-Hyacinthe, Québec, Canada.
| | | | | | | | | | | | | |
Collapse
|
15
|
Vijayakumar SRV, Kirchhof MG, Patten CL, Schellhorn HE. RpoS-regulated genes of Escherichia coli identified by random lacZ fusion mutagenesis. J Bacteriol 2005; 186:8499-507. [PMID: 15576800 PMCID: PMC532425 DOI: 10.1128/jb.186.24.8499-8507.2004] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
RpoS is a conserved alternative sigma factor that regulates the expression of many stress response genes in Escherichia coli. The RpoS regulon is large but has not yet been completely characterized. In this study, we report the identification of over 100 RpoS-dependent fusions in a genetic screen based on the differential expression of an operon-lacZ fusion bank in rpoS mutant and wild-type backgrounds. Forty-eight independent gene fusions were identified, including several in well-characterized RpoS-regulated genes, such as osmY, katE, and otsA. Many of the other fusions mapped to genes of unknown function or to genes that were not previously known to be under RpoS control. Based on the homology to other known bacterial genes, some of the RpoS-regulated genes of unknown functions are likely important in nutrient scavenging.
Collapse
|
16
|
Walz AC, Demel RA, de Kruijff B, Mutzel R. Aerobic sn-glycerol-3-phosphate dehydrogenase from Escherichia coli binds to the cytoplasmic membrane through an amphipathic alpha-helix. Biochem J 2002; 365:471-9. [PMID: 11955283 PMCID: PMC1222694 DOI: 10.1042/bj20011853] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2001] [Revised: 03/19/2002] [Accepted: 04/16/2002] [Indexed: 11/17/2022]
Abstract
sn-Glycerol-3-phosphate dehydrogenase (GlpD) from Escherichia coli is a peripheral membrane enzyme involved in respiratory electron transfer. For it to display its enzymic activity, binding to the inner membrane is required. The way the enzyme interacts with the membrane and how this controls activity has not been elucidated. In the present study we provide evidence for direct protein-lipid interaction. Using the monolayer technique, we observed insertion of GlpD into lipid monolayers with a clear preference for anionic phospholipids. GlpD variants with point mutations in their predicted amphipathic helices showed a decreased ability to penetrate anionic phospholipid monolayers. From these data we propose that membrane binding of GlpD occurs by insertion of an amphipathic helix into the acyl-chain region of lipids mediated by negatively charged phospholipids.
Collapse
|