1
|
Mittal P, Sinha AK, Pandiyan A, Kumari L, Ray MK, Pavankumar TL. A type II toxin-antitoxin system is responsible for the cell death at low temperature in Pseudomonas syringae Lz4W lacking RNase R. J Biol Chem 2024; 300:107600. [PMID: 39059490 PMCID: PMC11375266 DOI: 10.1016/j.jbc.2024.107600] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 06/17/2024] [Accepted: 07/12/2024] [Indexed: 07/28/2024] Open
Abstract
RNase R (encoded by the rnr gene) is a highly processive 3' → 5' exoribonuclease essential for the growth of the psychrotrophic bacterium Pseudomonas syringae Lz4W at low temperature. The cell death of a rnr deletion mutant at low temperature has been previously attributed to processing defects in 16S rRNA, defective ribosomal assembly, and inefficient protein synthesis. We recently showed that RNase R is required to protect P. syringae Lz4W from DNA damage and oxidative stress, independent of its exoribonuclease activity. Here, we show that the processing defect in 16S rRNA does not cause cell death of the rnr mutant of P. syringae at low temperature. Our results demonstrate that the rnr mutant of P. syringae Lz4W, complemented with a RNase R deficient in exoribonuclease function (RNase RD284A), is defective in 16S rRNA processing but can grow at 4 °C. This suggested that the processing defect in ribosomal RNAs is not a cause of the cold sensitivity of the rnr mutant. We further show that the rnr mutant accumulates copies of the indigenous plasmid pLz4W that bears a type II toxin-antitoxin (TA) system (P. syringae antitoxin-P. syringae toxin). This phenotype was rescued by overexpressing antitoxin psA in the rnr mutant, suggesting that activation of the type II TA system leads to cold sensitivity of the rnr mutant of P. syringae Lz4W. Here, we report a previously unknown functional relationship between the cold sensitivity of the rnr mutant and a type II TA system in P. syringae Lz4W.
Collapse
Affiliation(s)
- Pragya Mittal
- Centre for Cellular and Molecular Biology (CCMB), Council of Scientific and Industrial Research (CSIR), Hyderabad, India; Celtic Renewables Ltd, Edinburgh Napier University, Edinburgh, UK.
| | - Anurag K Sinha
- Centre for Cellular and Molecular Biology (CCMB), Council of Scientific and Industrial Research (CSIR), Hyderabad, India; National Food Institute, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Apuratha Pandiyan
- Centre for Cellular and Molecular Biology (CCMB), Council of Scientific and Industrial Research (CSIR), Hyderabad, India; Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Punjab, India
| | - Leela Kumari
- Centre for Cellular and Molecular Biology (CCMB), Council of Scientific and Industrial Research (CSIR), Hyderabad, India
| | - Malay K Ray
- Centre for Cellular and Molecular Biology (CCMB), Council of Scientific and Industrial Research (CSIR), Hyderabad, India
| | - Theetha L Pavankumar
- Centre for Cellular and Molecular Biology (CCMB), Council of Scientific and Industrial Research (CSIR), Hyderabad, India; Department of Microbiology and Molecular Genetics, University of California, Davis, California, USA; Department of Molecular and Cellular Biology, University of California, Davis, California, USA.
| |
Collapse
|
2
|
Ijaq J, Chandra D, Ray MK, Jagannadham MV. Investigating the Functional Role of Hypothetical Proteins From an Antarctic Bacterium Pseudomonas sp. Lz4W: Emphasis on Identifying Proteins Involved in Cold Adaptation. Front Genet 2022; 13:825269. [PMID: 35360867 PMCID: PMC8963723 DOI: 10.3389/fgene.2022.825269] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 02/07/2022] [Indexed: 11/28/2022] Open
Abstract
Exploring the molecular mechanisms behind bacterial adaptation to extreme temperatures has potential biotechnological applications. In the present study, Pseudomonas sp. Lz4W, a Gram-negative psychrophilic bacterium adapted to survive in Antarctica, was selected to decipher the molecular mechanism underlying the cold adaptation. Proteome analysis of the isolates grown at 4°C was performed to identify the proteins and pathways that are responsible for the adaptation. However, many proteins from the expressed proteome were found to be hypothetical proteins (HPs), whose function is unknown. Investigating the functional roles of these proteins may provide additional information in the biological understanding of the bacterial cold adaptation. Thus, our study aimed to assign functions to these HPs and understand their role at the molecular level. We used a structured insilico workflow combining different bioinformatics tools and databases for functional annotation. Pseudomonas sp. Lz4W genome (CP017432, version 1) contains 4493 genes and 4412 coding sequences (CDS), of which 743 CDS were annotated as HPs. Of these, from the proteome analysis, 61 HPs were found to be expressed consistently at the protein level. The amino acid sequences of these 61 HPs were submitted to our workflow and we could successfully assign a function to 18 HPs. Most of these proteins were predicted to be involved in biological mechanisms of cold adaptations such as peptidoglycan metabolism, cell wall organization, ATP hydrolysis, outer membrane fluidity, catalysis, and others. This study provided a better understanding of the functional significance of HPs in cold adaptation of Pseudomonas sp. Lz4W. Our approach emphasizes the importance of addressing the “hypothetical protein problem” for a thorough understanding of mechanisms at the cellular level, as well as, provided the assessment of integrating proteomics methods with various annotation and curation approaches to characterize hypothetical or uncharacterized protein data. The MS proteomics data generated from this study has been deposited to the ProteomeXchange through PRIDE with the dataset identifier–PXD029741.
Collapse
Affiliation(s)
- Johny Ijaq
- Metabolomics Facility, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Deepika Chandra
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Malay Kumar Ray
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - M. V. Jagannadham
- Metabolomics Facility, School of Life Sciences, University of Hyderabad, Hyderabad, India
- *Correspondence: M. V. Jagannadham,
| |
Collapse
|
3
|
Pavankumar TL, Mittal P, Hallsworth JE. Molecular insights into the ecology of a psychrotolerant
Pseudomonas syringae. Environ Microbiol 2020; 23:3665-3681. [DOI: 10.1111/1462-2920.15304] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 11/01/2020] [Accepted: 11/03/2020] [Indexed: 02/06/2023]
Affiliation(s)
- Theetha L. Pavankumar
- Department of Microbiology and Molecular Genetics, Briggs Hall, One Shields Avenue University of California Davis CA USA
| | - Pragya Mittal
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine University of Edinburgh Crewe Road South, Edinburgh, EH42XU, Scotland UK
| | - John E. Hallsworth
- Institute for Global Food Security, School of Biological Sciences Queen's University Belfast 19 Chlorine Gardens, Belfast, BT9 5DL Northern Ireland UK
| |
Collapse
|
4
|
Abstract
The ability to degrade the amino acid histidine to ammonia, glutamate, and a one-carbon compound (formate or formamide) is a property that is widely distributed among bacteria. The four or five enzymatic steps of the pathway are highly conserved, and the chemistry of the reactions displays several unusual features, including the rearrangement of a portion of the histidase polypeptide chain to yield an unusual imidazole structure at the active site and the use of a tightly bound NAD molecule as an electrophile rather than a redox-active element in urocanase. Given the importance of this amino acid, it is not surprising that the degradation of histidine is tightly regulated. The study of that regulation led to three central paradigms in bacterial regulation: catabolite repression by glucose and other carbon sources, nitrogen regulation and two-component regulators in general, and autoregulation of bacterial regulators. This review focuses on three groups of organisms for which studies are most complete: the enteric bacteria, for which the regulation is best understood; the pseudomonads, for which the chemistry is best characterized; and Bacillus subtilis, for which the regulatory mechanisms are very different from those of the Gram-negative bacteria. The Hut pathway is fundamentally a catabolic pathway that allows cells to use histidine as a source of carbon, energy, and nitrogen, but other roles for the pathway are also considered briefly here.
Collapse
|
5
|
Sundareswaran VR, Singh AK, Dube S, Shivaji S. Aspartate aminotransferase is involved in cold adaptation in psychrophilic Pseudomonas syringae. Arch Microbiol 2010; 192:663-72. [DOI: 10.1007/s00203-010-0591-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2010] [Revised: 05/19/2010] [Accepted: 05/21/2010] [Indexed: 11/28/2022]
|
6
|
Palonen E, Lindström M, Korkeala H. Adaptation of enteropathogenic Yersinia to low growth temperature. Crit Rev Microbiol 2010; 36:54-67. [PMID: 20088683 DOI: 10.3109/10408410903382581] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Yersinia enterocolitica and Yersinia pseudotuberculosis are important foodborne pathogens that cause infections through contaminated refrigerated food. Their cold tolerance mechanisms are therefore of special interest. Adaptation to cold involves changes in protein synthesis and in cell membranes to overcome diminished transcriptional and translational efficiency and reduced fluidity of cell membranes. Studies of low temperature adaptation mechanisms have mainly been performed on mesophilic bacteria, while most modern food hygiene risks are caused by psychrotrophs. Understanding low temperature adaptation of psychrotrophs would help to control these pathogens. This review demonstrates that more studies on cold tolerance mechanisms of psychrotrophs are needed.
Collapse
Affiliation(s)
- Eveliina Palonen
- Department of Food and Environmental Hygiene, University of Helsinki, Finland.
| | | | | |
Collapse
|
7
|
Importance of trmE for growth of the psychrophile Pseudomonas syringae at low temperatures. Appl Environ Microbiol 2009; 75:4419-26. [PMID: 19429554 DOI: 10.1128/aem.01523-08] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Transposon mutagenesis of Pseudomonas syringae Lz4W, a psychrophilic bacterium capable of growing at temperatures between 2 and 30 degrees C, yielded 30 cold-sensitive mutants, and CSM1, one of these cold-sensitive mutants, was characterized. Growth of CSM1 was retarded when it was cultured at 4 degrees C but not when it was cultured at 22 degrees C and 28 degrees C compared to the growth of wild-type cells, indicating that CSM1 is a cold-sensitive mutant of P. syringae Lz4W. The mutated gene in CSM1 was identified as trmE (coding for tRNA modification GTPase), and evidence is provided that this gene is induced at low temperatures. Further, the cold-inducible nature of the trmE promoter was demonstrated. In addition, the transcription start site and the various regulatory elements of the trmE promoter, such as the -10 region, -35 region, UP element, cold box, and DEAD box, were identified, and the importance of these regulatory elements in promoter activity were confirmed. The importance of trmE in rapid adaptation to growth at low temperatures was further highlighted by plasmid-mediated complementation that alleviated the cold-sensitive phenotype of CSM1.
Collapse
|
8
|
Sahu B, Ray MK. Auxotrophy in natural isolate: minimal requirements for growth of the Antarctic psychrotrophic bacteriumPseudomonas syringae Lz4W. J Basic Microbiol 2008; 48:38-47. [DOI: 10.1002/jobm.200700185] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
9
|
Makarova KS, Omelchenko MV, Gaidamakova EK, Matrosova VY, Vasilenko A, Zhai M, Lapidus A, Copeland A, Kim E, Land M, Mavromatis K, Pitluck S, Richardson PM, Detter C, Brettin T, Saunders E, Lai B, Ravel B, Kemner KM, Wolf YI, Sorokin A, Gerasimova AV, Gelfand MS, Fredrickson JK, Koonin EV, Daly MJ. Deinococcus geothermalis: the pool of extreme radiation resistance genes shrinks. PLoS One 2007; 2:e955. [PMID: 17895995 PMCID: PMC1978522 DOI: 10.1371/journal.pone.0000955] [Citation(s) in RCA: 177] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2007] [Accepted: 09/04/2007] [Indexed: 11/19/2022] Open
Abstract
Bacteria of the genus Deinococcus are extremely resistant to ionizing radiation (IR), ultraviolet light (UV) and desiccation. The mesophile Deinococcus radiodurans was the first member of this group whose genome was completely sequenced. Analysis of the genome sequence of D. radiodurans, however, failed to identify unique DNA repair systems. To further delineate the genes underlying the resistance phenotypes, we report the whole-genome sequence of a second Deinococcus species, the thermophile Deinococcus geothermalis, which at its optimal growth temperature is as resistant to IR, UV and desiccation as D. radiodurans, and a comparative analysis of the two Deinococcus genomes. Many D. radiodurans genes previously implicated in resistance, but for which no sensitive phenotype was observed upon disruption, are absent in D. geothermalis. In contrast, most D. radiodurans genes whose mutants displayed a radiation-sensitive phenotype in D. radiodurans are conserved in D. geothermalis. Supporting the existence of a Deinococcus radiation response regulon, a common palindromic DNA motif was identified in a conserved set of genes associated with resistance, and a dedicated transcriptional regulator was predicted. We present the case that these two species evolved essentially the same diverse set of gene families, and that the extreme stress-resistance phenotypes of the Deinococcus lineage emerged progressively by amassing cell-cleaning systems from different sources, but not by acquisition of novel DNA repair systems. Our reconstruction of the genomic evolution of the Deinococcus-Thermus phylum indicates that the corresponding set of enzymes proliferated mainly in the common ancestor of Deinococcus. Results of the comparative analysis weaken the arguments for a role of higher-order chromosome alignment structures in resistance; more clearly define and substantially revise downward the number of uncharacterized genes that might participate in DNA repair and contribute to resistance; and strengthen the case for a role in survival of systems involved in manganese and iron homeostasis.
Collapse
Affiliation(s)
- Kira S. Makarova
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, United States of America
- * To whom correspondence should be addressed. E-mail: (KM); (MD)
| | - Marina V. Omelchenko
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Elena K. Gaidamakova
- Department of Pathology, Uniformed Services University of the Health Sciences (USUHS), Bethesda, Maryland, United States of America
| | - Vera Y. Matrosova
- Department of Pathology, Uniformed Services University of the Health Sciences (USUHS), Bethesda, Maryland, United States of America
| | - Alexander Vasilenko
- Department of Pathology, Uniformed Services University of the Health Sciences (USUHS), Bethesda, Maryland, United States of America
| | - Min Zhai
- Department of Pathology, Uniformed Services University of the Health Sciences (USUHS), Bethesda, Maryland, United States of America
| | - Alla Lapidus
- US Department of Energy, Joint Genome Institute, Walnut Creek, California, United States of America
| | - Alex Copeland
- US Department of Energy, Joint Genome Institute, Walnut Creek, California, United States of America
| | - Edwin Kim
- US Department of Energy, Joint Genome Institute, Walnut Creek, California, United States of America
| | - Miriam Land
- US Department of Energy, Joint Genome Institute, Walnut Creek, California, United States of America
| | - Konstantinos Mavromatis
- US Department of Energy, Joint Genome Institute, Walnut Creek, California, United States of America
| | - Samuel Pitluck
- US Department of Energy, Joint Genome Institute, Walnut Creek, California, United States of America
| | - Paul M. Richardson
- US Department of Energy, Joint Genome Institute, Walnut Creek, California, United States of America
| | - Chris Detter
- US Department of Energy, Joint Genome Institute, Los Alamos National Laboratory, Los Alamos, New Mexico, United States of America
| | - Thomas Brettin
- US Department of Energy, Joint Genome Institute, Los Alamos National Laboratory, Los Alamos, New Mexico, United States of America
| | - Elizabeth Saunders
- US Department of Energy, Joint Genome Institute, Los Alamos National Laboratory, Los Alamos, New Mexico, United States of America
| | - Barry Lai
- Environmental Research Division and Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois, United States of America
| | - Bruce Ravel
- Environmental Research Division and Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois, United States of America
| | - Kenneth M. Kemner
- Environmental Research Division and Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois, United States of America
| | - Yuri I. Wolf
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Alexander Sorokin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Anna V. Gerasimova
- Research Institute of Genetics and Selection of Industrial Microorganisms, Moscow, Russia
| | - Mikhail S. Gelfand
- Institute for Information Transmission Problems of RAS, Moscow, Russia
- Faculty of Bioengineering and Bioinformatics, M. V. Lomonosov Moscow State University, Moscow, Russia
| | - James K. Fredrickson
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington, United States of America
| | - Eugene V. Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Michael J. Daly
- Department of Pathology, Uniformed Services University of the Health Sciences (USUHS), Bethesda, Maryland, United States of America
- * To whom correspondence should be addressed. E-mail: (KM); (MD)
| |
Collapse
|
10
|
Abstract
Survival of bacteria at low temperatures provokes scientific interest because of several reasons. Investigations in this area promise insight into one of the mysteries of life science - namely, how the machinery of life operates at extreme environments. Knowledge obtained from these studies is likely to be useful in controlling pathogenic bacteria, which survive and thrive in cold-stored food materials. The outcome of these studies may also help us to explore the possibilities of existence of life in distant frozen planets and their satellites.
Collapse
|
11
|
Bresolin G, Neuhaus K, Scherer S, Fuchs TM. Transcriptional analysis of long-term adaptation of Yersinia enterocolitica to low-temperature growth. J Bacteriol 2006; 188:2945-58. [PMID: 16585756 PMCID: PMC1447024 DOI: 10.1128/jb.188.8.2945-2958.2006] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To analyze the transcriptional response of Yersinia enterocolitica cells to prolonged growth at low temperature, a collection of luxCDABE transposon mutants was cultivated in parallel at optimal (30 degrees C) and suboptimal (10 degrees C) temperatures and screened for enhanced promoter activities during growth until entering stationary phase. Among 5,700 Y. enterocolitica mutants, 42 transcriptional units were identified with strongly enhanced or reduced promoter activity at 10 degrees C compared to 30 degrees C, and changes in their transcriptional levels over time were measured. Green fluorescent protein fusions to 10 promoter regions confirmed the data. The temporal order of induction of the temperature-responsive genes of Y. enterocolitica was deduced, starting with the expression of cold shock genes cspA and cspB and the elevated transcription of a glutamate-aspartate symporter. Subsequently, cold-adapted cells drastically up-regulated genes encoding environmental sensors and regulators, such as UhpABC, ArcA, and methyl-accepting chemotaxis protein I (MCPI). Among the most prominent cold-responsive elements that were transcriptionally induced during growth in early and middle exponential phase are the insecticidal toxin genes tcaA and tcaB, as well as genes involved in flagellar synthesis and chemotaxis. The expression pattern of the late-exponential- to early-stationary-growth phase is dominated by factors involved in biodegradative metabolism, namely, a histidine ammonia lyase, three enzymes responsible for uptake and utilization of glycogen, the urease complex, and a subtilisin-like protease. Double-knockout mutants and complementation studies demonstrate inhibitory effects of MCPI and UhpC on the expression of a putative hemolysin transporter. The data partially delineate the spectrum of gene expression of Y. enterocolitica at environmental temperatures, providing evidence that an as-yet-unknown insect phase is part of the life cycle of this human pathogen.
Collapse
Affiliation(s)
- Geraldine Bresolin
- Zentralinstitut für Ernährungs- und Lebensmittelforschung (ZIEL), Abteilung Mikrobiologie, Technische Universität München, Weihenstephaner Berg 3, D-85354 Freising, Germany
| | | | | | | |
Collapse
|
12
|
Regha K, Satapathy AK, Ray MK. RecD plays an essential function during growth at low temperature in the antarctic bacterium Pseudomonas syringae Lz4W. Genetics 2005; 170:1473-84. [PMID: 15956672 PMCID: PMC1449786 DOI: 10.1534/genetics.104.038943] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The Antarctic psychrotrophic bacterium Pseudomonas syringae Lz4W has been used as a model system to identify genes that are required for growth at low temperature. Transposon mutagenesis was carried out to isolate mutant(s) of the bacterium that are defective for growth at 4 degrees but normal at 22 degrees . In one such cold-sensitive mutant (CS1), the transposon-disrupted gene was identified to be a homolog of the recD gene of several bacteria. Trans-complementation and freshly targeted gene disruption studies reconfirmed that the inactivation of the recD gene leads to a cold-sensitive phenotype. We cloned, sequenced, and analyzed approximately 11.2 kbp of DNA from recD and its flanking region from the bacterium. recD was the last gene of a putative recCBD operon. The RecD ORF was 694 amino acids long and 40% identical (52% similar) to the Escherichia coli protein, and it could complement the E. coli recD mutation. The recD gene of E. coli, however, could not complement the cold-sensitive phenotype of the CS1 mutant. Interestingly, the CS1 strain showed greater sensitivity toward the DNA-damaging agents, mitomycin C and UV. The inactivation of recD in P. syringae also led to cell death and accumulation of DNA fragments of approximately 25-30 kbp in size at low temperature (4 degrees ). We propose that during growth at a very low temperature the Antarctic P. syringae is subjected to DNA damage, which requires direct participation of a unique RecD function. Additional results suggest that a truncated recD encoding the N-terminal segment of (1-576) amino acids is sufficient to support growth of P. syringae at low temperature.
Collapse
Affiliation(s)
- K Regha
- Centre for Cellular and Molecular Biology, Hyderabad 500007, India
| | | | | |
Collapse
|
13
|
Kapatral V, Campbell JW, Minnich SA, Thomson NR, Matsumura P, Prüß BM. Gene array analysis of Yersinia enterocolitica FlhD and FlhC: regulation of enzymes affecting synthesis and degradation of carbamoylphosphate. Microbiology (Reading) 2004; 150:2289-2300. [PMID: 15256571 DOI: 10.1099/mic.0.26814-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
This paper focuses on global gene regulation by FlhD/FlhC in enteric bacteria. Even though Yersinia enterocolitica FlhD/FlhC can complement an Escherichia coli
flhDC mutant for motility, it is not known if the Y. enterocolitica FlhD/FlhC complex has an effect on metabolism similar to E. coli. To study metabolic gene regulation, a partial Yersinia enterocolitica 8081c microarray was constructed and the expression patterns of wild-type cells were compared to an flhDC mutant strain at 25 and 37 °C. The overlap between the E. coli and Y. enterocolitica FlhD/FlhC regulated genes was 25 %. Genes that were regulated at least fivefold by FlhD/FlhC in Y. enterocolitica are genes encoding urocanate hydratase (hutU), imidazolone propionase (hutI), carbamoylphosphate synthetase (carAB) and aspartate carbamoyltransferase (pyrBI). These enzymes are part of a pathway that is involved in the degradation of l-histidine to l-glutamate and eventually leads into purine/pyrimidine biosynthesis via carbamoylphosphate and carbamoylaspartate. A number of other genes were regulated at a lower rate. In two additional experiments, the expression of wild-type cells grown at 4 or 25 °C was compared to the same strain grown at 37 °C. The expression of the flagella master operon flhD was not affected by temperature, whereas the flagella-specific sigma factor fliA was highly expressed at 25 °C and reduced at 4 and 37 °C. Several other flagella genes, all of which are under the control of FliA, exhibited a similar temperature profile. These data are consistent with the hypothesis that temperature regulation of flagella genes might be mediated by the flagella-specific sigma factor FliA and not the flagella master regulator FlhD/FlhC.
Collapse
Affiliation(s)
- Vinayak Kapatral
- Integrated Genomics, Inc., 2201 West Campbell Park Dr., Chicago, IL 60612, USA
| | - John W Campbell
- Integrated Genomics, Inc., 2201 West Campbell Park Dr., Chicago, IL 60612, USA
| | - Scott A Minnich
- Department of Microbiology, Molecular Biology and Biochemistry, University of Idaho, Moscow, ID 83843, USA
| | - Nicholas R Thomson
- The Wellcome Trust Sanger Institute, Genome Campus, Hinxton, Cambridge CB10 1RQ, UK
| | - Philip Matsumura
- Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, IL 60612-7344, USA
| | - Birgit M Prüß
- Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, IL 60612-7344, USA
| |
Collapse
|
14
|
Janiyani KL, Ray MK. Cloning, sequencing, and expression of the cold-inducible hutU gene from the antarctic psychrotrophic bacterium Pseudomonas syringae. Appl Environ Microbiol 2002; 68:1-10. [PMID: 11772602 PMCID: PMC126550 DOI: 10.1128/aem.68.1.1-10.2002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A promoter-fusion study with a Tn 5-based promoter probe vector had earlier found that the hutU gene which encodes the enzyme urocanase for the histidine utilization pathway is upregulated at a lower temperature (4 degrees C) in the Antarctic psychrotrophic bacterium Pseudomonas syringae. To examine the characteristics of the urocanase gene and its promoter elements from the psychrotroph, the complete hutU and its upstream region from P. syringae were cloned, sequenced, and analyzed in the present study. Northern blot and primer extension analyses suggested that the hutU gene is inducible upon a downshift of temperature (22 to 4 degrees C) and that there is more than one transcription initiation site. One of the initiation sites was specific to the cells grown at 4 degrees C, which was different from the common initiation sites observed at both 4 and 22 degrees C. Although no typical promoter consensus sequences were observed in the flanking region of the transcription initiation sites, there was a characteristic CAAAA sequence at the -10 position of the promoters. Additionally, the location of the transcription and translation initiation sites suggested that the hutU mRNA contains a long 5'-untranslated region, a characteristic feature of many cold-inducible genes of mesophilic bacteria. A comparison of deduced amino acid sequences of urocanase from various bacteria, including the mesophilic and psychrotrophic Pseudomonas spp., suggests that there is a high degree of similarity between the enzymes. The enzyme sequence contains a signature motif (GXGX(2)GX(10)G) of the Rossmann fold for dinucleotide (NAD(+)) binding and two conserved cysteine residues in and around the active site. The psychrotrophic enzyme, however, has an extended N-terminal end.
Collapse
|
15
|
Adaptation to low temperature and regulation of gene expression in antarctic psychrotrophic bacteria. J Biosci 1998. [DOI: 10.1007/bf02936136] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|