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Nie X, Yang B, Zhang L, Gu Y, Yang S, Jiang W, Yang C. PTS regulation domain-containing transcriptional activator CelR and sigma factor σ54control cellobiose utilization inClostridium acetobutylicum. Mol Microbiol 2016; 100:289-302. [DOI: 10.1111/mmi.13316] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/16/2015] [Indexed: 11/27/2022]
Affiliation(s)
- Xiaoqun Nie
- Key Laboratory of Synthetic Biology; Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; Shanghai 200032 China
| | - Bin Yang
- Key Laboratory of Synthetic Biology; Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; Shanghai 200032 China
| | - Lei Zhang
- Key Laboratory of Synthetic Biology; Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; Shanghai 200032 China
| | - Yang Gu
- Key Laboratory of Synthetic Biology; Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; Shanghai 200032 China
| | - Sheng Yang
- Key Laboratory of Synthetic Biology; Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; Shanghai 200032 China
| | - Weihong Jiang
- Key Laboratory of Synthetic Biology; Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; Shanghai 200032 China
| | - Chen Yang
- Key Laboratory of Synthetic Biology; Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; Shanghai 200032 China
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Accumulation of polyphosphate in Lactobacillus spp. and its involvement in stress resistance. Appl Environ Microbiol 2013; 80:1650-9. [PMID: 24375133 DOI: 10.1128/aem.03997-13] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Polyphosphate (poly-P) is a polymer of phosphate residues synthesized and in some cases accumulated by microorganisms, where it plays crucial physiological roles such as the participation in the response to nutritional stringencies and environmental stresses. Poly-P metabolism has received little attention in Lactobacillus, a genus of lactic acid bacteria of relevance for food production and health of humans and animals. We show that among 34 strains of Lactobacillus, 18 of them accumulated intracellular poly-P granules, as revealed by specific staining and electron microscopy. Poly-P accumulation was generally dependent on the presence of elevated phosphate concentrations in the culture medium, and it correlated with the presence of polyphosphate kinase (ppk) genes in the genomes. The ppk gene from Lactobacillus displayed a genetic arrangement in which it was flanked by two genes encoding exopolyphosphatases of the Ppx-GppA family. The ppk functionality was corroborated by its disruption (LCABL_27820 gene) in Lactobacillus casei BL23 strain. The constructed ppk mutant showed a lack of intracellular poly-P granules and a drastic reduction in poly-P synthesis. Resistance to several stresses was tested in the ppk-disrupted strain, showing that it presented a diminished growth under high-salt or low-pH conditions and an increased sensitivity to oxidative stress. These results show that poly-P accumulation is a characteristic of some strains of lactobacilli and may thus play important roles in the physiology of these microorganisms.
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Francke C, Groot Kormelink T, Hagemeijer Y, Overmars L, Sluijter V, Moezelaar R, Siezen RJ. Comparative analyses imply that the enigmatic Sigma factor 54 is a central controller of the bacterial exterior. BMC Genomics 2011; 12:385. [PMID: 21806785 PMCID: PMC3162934 DOI: 10.1186/1471-2164-12-385] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Accepted: 08/01/2011] [Indexed: 02/06/2023] Open
Abstract
Background Sigma-54 is a central regulator in many pathogenic bacteria and has been linked to a multitude of cellular processes like nitrogen assimilation and important functional traits such as motility, virulence, and biofilm formation. Until now it has remained obscure whether these phenomena and the control by Sigma-54 share an underlying theme. Results We have uncovered the commonality by performing a range of comparative genome analyses. A) The presence of Sigma-54 and its associated activators was determined for all sequenced prokaryotes. We observed a phylum-dependent distribution that is suggestive of an evolutionary relationship between Sigma-54 and lipopolysaccharide and flagellar biosynthesis. B) All Sigma-54 activators were identified and annotated. The relation with phosphotransfer-mediated signaling (TCS and PTS) and the transport and assimilation of carboxylates and nitrogen containing metabolites was substantiated. C) The function annotations, that were represented within the genomic context of all genes encoding Sigma-54, its activators and its promoters, were analyzed for intra-phylum representation and inter-phylum conservation. Promoters were localized using a straightforward scoring strategy that was formulated to identify similar motifs. We found clear highly-represented and conserved genetic associations with genes that concern the transport and biosynthesis of the metabolic intermediates of exopolysaccharides, flagella, lipids, lipopolysaccharides, lipoproteins and peptidoglycan. Conclusion Our analyses directly implicate Sigma-54 as a central player in the control over the processes that involve the physical interaction of an organism with its environment like in the colonization of a host (virulence) or the formation of biofilm.
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Affiliation(s)
- Christof Francke
- TI Food and Nutrition, P,O,Box 557, 6700AN Wageningen, The Netherlands.
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Wu R, Zhang W, Sun T, Wu J, Yue X, Meng H, Zhang H. Proteomic analysis of responses of a new probiotic bacterium Lactobacillus casei Zhang to low acid stress. Int J Food Microbiol 2011; 147:181-7. [DOI: 10.1016/j.ijfoodmicro.2011.04.003] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2010] [Revised: 03/25/2011] [Accepted: 04/05/2011] [Indexed: 10/18/2022]
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Liu M, Bayjanov JR, Renckens B, Nauta A, Siezen RJ. The proteolytic system of lactic acid bacteria revisited: a genomic comparison. BMC Genomics 2010; 11:36. [PMID: 20078865 PMCID: PMC2827410 DOI: 10.1186/1471-2164-11-36] [Citation(s) in RCA: 197] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2009] [Accepted: 01/15/2010] [Indexed: 12/30/2022] Open
Abstract
Background Lactic acid bacteria (LAB) are a group of gram-positive, lactic acid producing Firmicutes. They have been extensively used in food fermentations, including the production of various dairy products. The proteolytic system of LAB converts proteins to peptides and then to amino acids, which is essential for bacterial growth and also contributes significantly to flavor compounds as end-products. Recent developments in high-throughput genome sequencing and comparative genomics hybridization arrays provide us with opportunities to explore the diversity of the proteolytic system in various LAB strains. Results We performed a genome-wide comparative genomics analysis of proteolytic system components, including cell-wall bound proteinase, peptide transporters and peptidases, in 22 sequenced LAB strains. The peptidase families PepP/PepQ/PepM, PepD and PepI/PepR/PepL are described as examples of our in silico approach to refine the distinction of subfamilies with different enzymatic activities. Comparison of protein 3D structures of proline peptidases PepI/PepR/PepL and esterase A allowed identification of a conserved core structure, which was then used to improve phylogenetic analysis and functional annotation within this protein superfamily. The diversity of proteolytic system components in 39 Lactococcus lactis strains was explored using pangenome comparative genome hybridization analysis. Variations were observed in the proteinase PrtP and its maturation protein PrtM, in one of the Opp transport systems and in several peptidases between strains from different Lactococcus subspecies or from different origin. Conclusions The improved functional annotation of the proteolytic system components provides an excellent framework for future experimental validations of predicted enzymatic activities. The genome sequence data can be coupled to other "omics" data e.g. transcriptomics and metabolomics for prediction of proteolytic and flavor-forming potential of LAB strains. Such an integrated approach can be used to tune the strain selection process in food fermentations.
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Affiliation(s)
- Mengjin Liu
- Centre for Molecular and Biomolecular Informatics, Radboud University Medical Centre, Nijmegen, the Netherlands.
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Stevens MJA, Molenaar D, de Jong A, De Vos WM, Kleerebezem M. sigma54-Mediated control of the mannose phosphotransferase sytem in Lactobacillus plantarum impacts on carbohydrate metabolism. MICROBIOLOGY-SGM 2009; 156:695-707. [PMID: 19942662 DOI: 10.1099/mic.0.034165-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Sigma factors direct specific binding of the bacterial RNA polymerase to the promoter. Here we present the elucidation of the sigma(54 ) regulon in Lactobacillus plantarum. A sequence-based regulon prediction of sigma(54)-dependent promoters revealed an operon encoding a mannose phosphotransferase system (PTS) as the best candidate for sigma(54)-mediated control. A sigma (54) (rpoN) mutant derivative did not grow on mannose, confirming this prediction. Additional mutational analyses established the presence of one functional mannose PTS in L. plantarum, the expression of which is controlled by sigma(54) in concert with the sigma(54)-activator ManR. Genome-wide transcription comparison of the wild-type and the rpoN-deletion strain revealed nine upregulated genes in the wild-type, including the genes of the mannose PTS, and 21 upregulated genes in the rpoN mutant. The sigma(54)-controlled mannose PTS was shown also to transport glucose in L. plantarum wild-type cells, and its presence causes a lag phase when cultures are transferred from glucose- to galactose-containing media. The mannose PTS appeared to drain phosphoenolpyruvate (PEP) pools in resting cells, since no PEP could be detected in resting wild-type cells, while mannose PTS mutant derivatives contained 1-3 muM PEP (mg protein)(-1 ). Our data provide new insight into the role of sigma( 54) in L. plantarum and possibly other Gram-positive bacteria in the control of expression of an important glucose transporter that contributes to glucose-mediated catabolite control via modulation of the PEP pool.
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Affiliation(s)
- Marc J A Stevens
- NIZO food research, PO Box 20, 6710 BA Ede, The Netherlands.,TI Food and Nutrition, PO Box 557, 6700 AN Wageningen, The Netherlands.,Laboratory of Microbiology, Wageningen University and Research Centre, Dreijenplein 10, 6703 HB Wageningen, The Netherlands
| | - Douwe Molenaar
- NIZO food research, PO Box 20, 6710 BA Ede, The Netherlands.,TI Food and Nutrition, PO Box 557, 6700 AN Wageningen, The Netherlands
| | - Anne de Jong
- Department of Genetics, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), Rijksuniversiteit Groningen, Kerklaan 30, 9751 NN Haren, The Netherlands
| | - Willem M De Vos
- Laboratory of Microbiology, Wageningen University and Research Centre, Dreijenplein 10, 6703 HB Wageningen, The Netherlands.,TI Food and Nutrition, PO Box 557, 6700 AN Wageningen, The Netherlands
| | - Michiel Kleerebezem
- Laboratory of Microbiology, Wageningen University and Research Centre, Dreijenplein 10, 6703 HB Wageningen, The Netherlands.,NIZO food research, PO Box 20, 6710 BA Ede, The Netherlands.,TI Food and Nutrition, PO Box 557, 6700 AN Wageningen, The Netherlands
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Wu R, Wang W, Yu D, Zhang W, Li Y, Sun Z, Wu J, Meng H, Zhang H. Proteomics analysis of Lactobacillus casei Zhang, a new probiotic bacterium isolated from traditional home-made koumiss in Inner Mongolia of China. Mol Cell Proteomics 2009; 8:2321-38. [PMID: 19508964 PMCID: PMC2758759 DOI: 10.1074/mcp.m800483-mcp200] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2008] [Revised: 03/16/2009] [Indexed: 11/06/2022] Open
Abstract
Lactobacillus casei Zhang, isolated from traditional home-made koumiss in Inner Mongolia of China, was considered as a new probiotic bacterium by probiotic selection tests. We carried out a proteomics study to identify and characterize proteins expressed by L. casei Zhang in the exponential phase and stationary phase. Cytosolic proteins of the strain cultivated in de Man, Rogosa, and Sharpe broth were resolved by two-dimensional gel electrophoresis using pH 4-7 linear gradients. The number of protein spots quantified from the gels was 487 +/- 21 (exponential phase) and 494 +/- 13 (stationary phase) among which a total of 131 spots were identified by MALDI-TOF/MS and/or MALDI-TOF/TOF according to significant growth phase-related differences or high expression intensity proteins. Accompanied by the cluster of orthologous groups (COG), codon adaptation index (CAI), and GRAVY value analysis, the study provided a very first insight into the profile of protein expression as a reference map of L. casei. Forty-seven spots were also found in the study that showed statistically significant differences between exponential phase and stationary phase. Thirty-three of the spots increased at least 2.5-fold in the stationary phase in comparison with the exponential phase, including 19 protein spots (e.g. Hsp20, DnaK, GroEL, LuxS, pyruvate kinase, and GalU) whose intensity up-shifted above 3.0-fold. Transcriptional profiles were conducted to confirm several important differentially expressed proteins by using real time quantitative PCR. The analysis suggests that the differentially expressed proteins were mainly categorized as stress response proteins and key components of central and intermediary metabolism, indicating that these proteins might play a potential important role for the adaptation to the surroundings, especially the accumulation of lactic acid in the course of growth, and the physiological processes in bacteria cell.
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Affiliation(s)
- Rina Wu
- From the ‡The Key Laboratory of Dairy Biotechnology and Bioengineering, Ministry of Education, Department of Food Science and Engineering, Inner Mongolia Agricultural University, Hohhot 010018, China
- §College of Food Science, Shenyang Agricultural University, Shenyang 11061, China
| | - Weiwei Wang
- ¶Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100080, China, and
| | - Dongliang Yu
- ¶Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100080, China, and
| | - Wenyi Zhang
- From the ‡The Key Laboratory of Dairy Biotechnology and Bioengineering, Ministry of Education, Department of Food Science and Engineering, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Yan Li
- From the ‡The Key Laboratory of Dairy Biotechnology and Bioengineering, Ministry of Education, Department of Food Science and Engineering, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Zhihong Sun
- From the ‡The Key Laboratory of Dairy Biotechnology and Bioengineering, Ministry of Education, Department of Food Science and Engineering, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Junrui Wu
- §College of Food Science, Shenyang Agricultural University, Shenyang 11061, China
| | - He Meng
- ‖School of Agricultural and Biological, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Heping Zhang
- From the ‡The Key Laboratory of Dairy Biotechnology and Bioengineering, Ministry of Education, Department of Food Science and Engineering, Inner Mongolia Agricultural University, Hohhot 010018, China
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Regulation of Lactobacillus casei sorbitol utilization genes requires DNA-binding transcriptional activator GutR and the conserved protein GutM. Appl Environ Microbiol 2008; 74:5731-40. [PMID: 18676710 DOI: 10.1128/aem.00230-08] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sequence analysis of the five genes (gutRMCBA) downstream from the previously described sorbitol-6-phosphate dehydrogenase-encoding Lactobacillus casei gutF gene revealed that they constitute a sorbitol (glucitol) utilization operon. The gutRM genes encode putative regulators, while the gutCBA genes encode the EIIC, EIIBC, and EIIA proteins of a phosphoenolpyruvate-dependent sorbitol phosphotransferase system (PTS(Gut)). The gut operon is transcribed as a polycistronic gutFRMCBA messenger, the expression of which is induced by sorbitol and repressed by glucose. gutR encodes a transcriptional regulator with two PTS-regulated domains, a galactitol-specific EIIB-like domain (EIIB(Gat) domain) and a mannitol/fructose-specific EIIA-like domain (EIIA(Mtl) domain). Its inactivation abolished gut operon transcription and sorbitol uptake, indicating that it acts as a transcriptional activator. In contrast, cells carrying a gutB mutation expressed the gut operon constitutively, but they failed to transport sorbitol, indicating that EIIBC(Gut) negatively regulates GutR. A footprint analysis showed that GutR binds to a 35-bp sequence upstream from the gut promoter. A sequence comparison with the presumed promoter region of gut operons from various firmicutes revealed a GutR consensus motif that includes an inverted repeat. The regulation mechanism of the L. casei gut operon is therefore likely to be operative in other firmicutes. Finally, gutM codes for a conserved protein of unknown function present in all sequenced gut operons. A gutM mutant, the first constructed in a firmicute, showed drastically reduced gut operon expression and sorbitol uptake, indicating a regulatory role also for GutM.
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Liu M, Nauta A, Francke C, Siezen RJ. Comparative genomics of enzymes in flavor-forming pathways from amino acids in lactic acid bacteria. Appl Environ Microbiol 2008; 74:4590-600. [PMID: 18539796 PMCID: PMC2519355 DOI: 10.1128/aem.00150-08] [Citation(s) in RCA: 135] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Affiliation(s)
- Mengjin Liu
- Centre for Molecular and Biomolecular Informatics, Radboud University Nijmegen Medical Centre, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands.
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Xue J, Miller KW. Regulation of the mpt operon in Listeria innocua by the ManR protein. Appl Environ Microbiol 2007; 73:5648-52. [PMID: 17616620 PMCID: PMC2042094 DOI: 10.1128/aem.00052-07] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The phosphotransferase system regulation domain (PRD)-containing activator, ManR, is required for glucose-controlled transcription of the mannose permease two (mpt) operon in Listeria innocua. His-871 in ManR PRD-II is needed for mpt repression in glucose-free media. His-506 in PRD-I is needed for mpt induction by glucose.
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Affiliation(s)
- Junfeng Xue
- Department of Molecular Biology, University of Wyoming, 1000 E. University Avenue, Dept. 3944, Laramie, WY 82071-3944, USA
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Deutscher J, Francke C, Postma PW. How phosphotransferase system-related protein phosphorylation regulates carbohydrate metabolism in bacteria. Microbiol Mol Biol Rev 2007; 70:939-1031. [PMID: 17158705 PMCID: PMC1698508 DOI: 10.1128/mmbr.00024-06] [Citation(s) in RCA: 985] [Impact Index Per Article: 57.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The phosphoenolpyruvate(PEP):carbohydrate phosphotransferase system (PTS) is found only in bacteria, where it catalyzes the transport and phosphorylation of numerous monosaccharides, disaccharides, amino sugars, polyols, and other sugar derivatives. To carry out its catalytic function in sugar transport and phosphorylation, the PTS uses PEP as an energy source and phosphoryl donor. The phosphoryl group of PEP is usually transferred via four distinct proteins (domains) to the transported sugar bound to the respective membrane component(s) (EIIC and EIID) of the PTS. The organization of the PTS as a four-step phosphoryl transfer system, in which all P derivatives exhibit similar energy (phosphorylation occurs at histidyl or cysteyl residues), is surprising, as a single protein (or domain) coupling energy transfer and sugar phosphorylation would be sufficient for PTS function. A possible explanation for the complexity of the PTS was provided by the discovery that the PTS also carries out numerous regulatory functions. Depending on their phosphorylation state, the four proteins (domains) forming the PTS phosphorylation cascade (EI, HPr, EIIA, and EIIB) can phosphorylate or interact with numerous non-PTS proteins and thereby regulate their activity. In addition, in certain bacteria, one of the PTS components (HPr) is phosphorylated by ATP at a seryl residue, which increases the complexity of PTS-mediated regulation. In this review, we try to summarize the known protein phosphorylation-related regulatory functions of the PTS. As we shall see, the PTS regulation network not only controls carbohydrate uptake and metabolism but also interferes with the utilization of nitrogen and phosphorus and the virulence of certain pathogens.
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Affiliation(s)
- Josef Deutscher
- Microbiologie et Génétique Moléculaire, INRA-CNRS-INA PG UMR 2585, Thiverval-Grignon, France.
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Velasco SE, Yebra MJ, Monedero V, Ibarburu I, Dueñas MT, Irastorza A. Influence of the carbohydrate source on beta-glucan production and enzyme activities involved in sugar metabolism in Pediococcus parvulus 2.6. Int J Food Microbiol 2007; 115:325-34. [PMID: 17303279 DOI: 10.1016/j.ijfoodmicro.2006.12.023] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2006] [Accepted: 12/07/2006] [Indexed: 10/23/2022]
Abstract
The influence of carbohydrate source on growth, exopolysaccharide (EPS) production and on the activity of the enzymes implicated in energy generation and UDP-glucose synthesis in Pediococcus parvulus 2.6 was evaluated. The highest EPS production was obtained on glucose, while fructose was a poor substrate for EPS synthesis. HPLC and NMR analysis on monomer composition and structure of the EPS showed that this strain produced the same beta-glucan, regardless of the carbohydrate source. The alpha-phosphoglucomutase specific activities were dependent on the carbohydrate source and a high correlation between the activity of this enzyme and the amount of EPS was found in glucose- and maltose-grown cultures. alpha-UDP-glucose pyrophosphorylase activity, necessary for the activation of glucose, was very low, but significantly higher on glucose as sugar source. In vitro phosphorylation assays and transport activities showed that glucose is taken up by a proton motive force-dependent permease, while fructose is internalized by an inducible phosphotransferase system, which renders fructose-6-phosphate. The levels of 6-phosphofructokinase activity and alpha-phosphoglucomutase activities determined on fructose were higher and lower, than those found on glucose or maltose, respectively. This suggests that fructose-6-phosphate is mainly diverted to glycolysis and explains the low EPS synthesis on fructose. Results indicate that alpha-phosphoglucomutase and/or alpha-UDP-glucose pyrophosphorylase might be the bottlenecks for EPS biosynthesis, opening the field for metabolic-engineering strategies aimed to improve EPS production.
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Affiliation(s)
- S E Velasco
- Departamento de Química Aplicada, Facultad de Ciencias Químicas, Universidad del País Vasco, Box 1072, 20080, San Sebastián, Spain.
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Monedero V, Mazé A, Boël G, Zúñiga M, Beaufils S, Hartke A, Deutscher J. The Phosphotransferase System of Lactobacillus casei: Regulation of Carbon Metabolism and Connection to Cold Shock Response. J Mol Microbiol Biotechnol 2006; 12:20-32. [PMID: 17183208 DOI: 10.1159/000096456] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Genome sequencing of two different Lactobacillus casei strains (ATCC334 and BL23) is presently going on and preliminary data revealed that this lactic acid bacterium possesses numerous carbohydrate transport systems probably reflecting its capacity to proliferate under varying environmental conditions. Many carbohydrate transporters belong to the phosphoenolpyruvate:sugar phosphotransferase system (PTS), but all different kinds of non-PTS transporters are present as well and their substrates are known in a few cases. In L. casei regulation of carbohydrate transport and carbon metabolism is mainly achieved by PTS proteins. Carbon catabolite repression (CCR) is mediated via several mechanisms, including the major P-Ser-HPr/catabolite control protein A (CcpA)-dependent mechanism. Catabolite response elements, the target sites for the P-Ser-HPr/CcpA complex, precede numerous genes and operons. PTS regulation domain-containing antiterminators and transcription activators are also present in both L. casei strains. Their activity is usually controlled by two PTS-mediated phosphorylation reactions exerting antagonistic effects on the transcription regulators: P~EIIB-dependent phosphorylation regulates induction of the corresponding genes and P~His-HPr-mediated phosphorylation plays a role in CCR. Carbohydrate transport of L. casei is also regulated via inducer exclusion and inducer expulsion. The presence of glucose, fructose, etc. leads to inhibition of the transport or metabolism of less favorable carbon sources (inducer exclusion) or to the export of accumulated non-metabolizable carbon sources (inducer expulsion). While P-Ser-HPr is essential for inducer exclusion of maltose, it is not necessary for the expulsion of accumulated thio-methyl-beta-D-galactopyranoside. Surprisingly, recent evidence suggests that the PTS of L. casei also plays a role in cold shock response.
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Affiliation(s)
- Vicente Monedero
- Departamento de Biotecnología, Instituto de Agroquímica y Tecnología de Alimentos, CSIC, Burjassot, Spain
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Yebra MJ, Monedero V, Zúñiga M, Deutscher J, Pérez-Martínez G. Molecular analysis of the glucose-specific phosphoenolpyruvate : sugar phosphotransferase system from Lactobacillus casei and its links with the control of sugar metabolism. Microbiology (Reading) 2006; 152:95-104. [PMID: 16385119 DOI: 10.1099/mic.0.28293-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Lactobacillus caseitransports glucose preferentially by a mannose-class phosphoenolpyruvate : sugar phosphotransferase system (PTS). The genomic analysis ofL. caseiallowed the authors to find a gene cluster (manLMNO) encoding the IIAB (manL), IIC (manM) and IID (manN) proteins of a mannose-class PTS, and a putative 121 aa protein of unknown function (encoded bymanO), homologues of which are also present inmanclusters that encode glucose/mannose transporters in other Gram-positive bacteria. TheL. casei manoperon is constitutively expressed into amanLMNOmessenger, but an additionalmanOtranscript was also detected. Upstream of themanoperon, two genes (upsRandupsA) were found which encode proteins resembling a transcriptional regulator and a membrane protein, respectively. Disruption of eitherupsRorupsAdid not affectmanLMNOtranscription, and had no effect on glucose uptake. Cells carrying amanOdeletion transported glucose at a rate similar to that of the wild-type strain. By contrast, amanMdisruption resulted in cells unable to transport glucose by the PTS, thus confirming the functional role of themangenes. In addition, themanMmutant exhibited neither inducer exclusion of maltose nor glucose repression. This result confirms the need for glucose transport through the PTS to trigger these regulatory processes inL. casei.
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Affiliation(s)
- María J Yebra
- Departamento de Biotecnología, Instituto de Agroquímica y Tecnología de Alimentos, CSIC, Apdo. Correos 73, 46100 Burjassot, Spain
| | - Vicente Monedero
- Departamento de Biotecnología, Instituto de Agroquímica y Tecnología de Alimentos, CSIC, Apdo. Correos 73, 46100 Burjassot, Spain
| | - Manuel Zúñiga
- Departamento de Biotecnología, Instituto de Agroquímica y Tecnología de Alimentos, CSIC, Apdo. Correos 73, 46100 Burjassot, Spain
| | - Josef Deutscher
- Microbiologie et Génétique Moléculaire, CNRS/INRA/INA-PG, UMR2585, 78850 Thiverval-Grignon, France
| | - Gaspar Pérez-Martínez
- Departamento de Biotecnología, Instituto de Agroquímica y Tecnología de Alimentos, CSIC, Apdo. Correos 73, 46100 Burjassot, Spain
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