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Pei H, Zhu C, Shu F, Lu Z, Wang H, Ma K, Wang J, Lan R, Shang F, Xue T. CodY: An Essential Transcriptional Regulator Involved in Environmental Stress Tolerance in Foodborne Staphylococcus aureus RMSA24. Foods 2023; 12:3166. [PMID: 37685098 PMCID: PMC10486358 DOI: 10.3390/foods12173166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/04/2023] [Accepted: 08/15/2023] [Indexed: 09/10/2023] Open
Abstract
Staphylococcus aureus (S. aureus), as the main pathogen in milk and dairy products, usually causes intoxication with vomiting and various kinds of inflammation after entering the human body. CodY, an important transcriptional regulator in S. aureus, plays an important role in regulating metabolism, growth, and virulence. However, little is known about the role of CodY on environmental stress tolerance. In this research, we revealed the role of CodY in environmental stress tolerance in foodborne S. aureus RMSA24. codY mutation significantly reduced the tolerance of S. aureus to desiccation and oxidative, salt, and high-temperature stresses. However, S. aureus was more tolerant to low temperature stress due to mutation of codY. We found that the expressions of two important heat shock proteins-GroEL and DanJ-were significantly down-regulated in the mutant codY. This suggests that CodY may indirectly regulate the high- and low-temperature tolerance of S. aureus by regulating the expressions of groEL and danJ. This study reveals a new mechanism of environmental stress tolerance in S. aureus and provides new insights into controlling the contamination and harm caused by S. aureus in the food industry.
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Affiliation(s)
- Hao Pei
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, China; (H.P.); (C.Z.); (F.S.); (Z.L.); (H.W.); (K.M.); (J.W.); (R.L.); (F.S.)
| | - Chengfeng Zhu
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, China; (H.P.); (C.Z.); (F.S.); (Z.L.); (H.W.); (K.M.); (J.W.); (R.L.); (F.S.)
| | - Fang Shu
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, China; (H.P.); (C.Z.); (F.S.); (Z.L.); (H.W.); (K.M.); (J.W.); (R.L.); (F.S.)
| | - Zhengfei Lu
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, China; (H.P.); (C.Z.); (F.S.); (Z.L.); (H.W.); (K.M.); (J.W.); (R.L.); (F.S.)
| | - Hui Wang
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, China; (H.P.); (C.Z.); (F.S.); (Z.L.); (H.W.); (K.M.); (J.W.); (R.L.); (F.S.)
| | - Kai Ma
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, China; (H.P.); (C.Z.); (F.S.); (Z.L.); (H.W.); (K.M.); (J.W.); (R.L.); (F.S.)
| | - Jun Wang
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, China; (H.P.); (C.Z.); (F.S.); (Z.L.); (H.W.); (K.M.); (J.W.); (R.L.); (F.S.)
| | - Ranxiang Lan
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, China; (H.P.); (C.Z.); (F.S.); (Z.L.); (H.W.); (K.M.); (J.W.); (R.L.); (F.S.)
| | - Fei Shang
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, China; (H.P.); (C.Z.); (F.S.); (Z.L.); (H.W.); (K.M.); (J.W.); (R.L.); (F.S.)
- Food Procession Research Institute, Anhui Agricultural University, Hefei 230036, China
| | - Ting Xue
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, China; (H.P.); (C.Z.); (F.S.); (Z.L.); (H.W.); (K.M.); (J.W.); (R.L.); (F.S.)
- Food Procession Research Institute, Anhui Agricultural University, Hefei 230036, China
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Wang H, Hou X, Shen J, Wang W, Ye Y, Yu J, Xue T. Alternative sigma factor B reduces biofilm formation and stress response in milk-derived Staphylococcus aureus. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.113515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Chen JC, Chang CF, Hsu DW, Shu JC, Chen HY, Chen CY, Lu CY, Chen CC. Temporal regulation of σ B by partner-switching mechanism at a distinct growth stage in Bacillus cereus. Int J Med Microbiol 2017; 307:521-532. [PMID: 28919098 DOI: 10.1016/j.ijmm.2017.09.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 08/15/2017] [Accepted: 09/04/2017] [Indexed: 12/01/2022] Open
Abstract
The alternative transcription factor σB in Bacillus cereus governs the transcription of a number of genes that confer protection against general stress. This transcription factor is regulated by protein-protein interactions among RsbV, RsbW, σB, RsbY, RsbM and RsbK, all encoded in the sigB cluster. Among these regulatory proteins, RsbV, RsbW and σB comprise a partner-switching mechanism. Under normal conditions, σB remains inactive by associating with anti-sigma factor RsbW, which prevents σB from binding to the core RNA polymerase. During environmental stress, RsbK activates RsbY to hydrolyze phosphorylated RsbV, and the dephosphorylated RsbV then sequesters RsbW to liberate σB from RsbW. Although the σB partner-switching module is thought to be the core mechanism for σB regulation, the actual protein-protein interactions among these three proteins in the cell remain to be investigated. In the current study, we show that RsbW and RsbV form a long-lived complex under transient stress treatment, resulting in high persistent expression of RsbV, RsbW and σB from mid-log phase to stationary phase. Full sequestration of RsbW by excess RsbV and increased RsbW:RsbV complex stability afforded by cellular ADP contribute to the prolonged activation of σB. Interestingly, the high expression levels of RsbV, RsbW and σB were dramatically decreased beginning from the transition stage to the stationary phase. Thus, protein interactions among σB partner-switching components are required for the continued induction of σB during environmental stress in the log phase and significant down-regulation of σB is observed in the stationary phase. Our data show that σB is temporally regulated in B. cereus.
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Affiliation(s)
- Jung-Chi Chen
- Department of Biotechnology, National Kaohsiung Normal University, 62 Shenjhong Road, Yanchao District, Kaohsiung 82444, Taiwan
| | - Chuan-Fu Chang
- Department of Biotechnology, National Kaohsiung Normal University, 62 Shenjhong Road, Yanchao District, Kaohsiung 82444, Taiwan
| | - Duen-Wei Hsu
- Department of Biotechnology, National Kaohsiung Normal University, 62 Shenjhong Road, Yanchao District, Kaohsiung 82444, Taiwan
| | - Jwu-Ching Shu
- Department of Medical Biotechnology and Laboratory Science, Chang Gung University, Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan County 333, Taiwan
| | - Hong-Yi Chen
- Department of Medical Biotechnology and Laboratory Science, Chang Gung University, Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan County 333, Taiwan
| | - Chien-Yen Chen
- Department of Earth and Environmental Sciences, National Chung Cheng University, 168 University Road, Min-Hsiung, Chiayi 62102, Taiwan
| | - Chi-Yu Lu
- Department of Biochemistry, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Chien-Cheng Chen
- Department of Biotechnology, National Kaohsiung Normal University, 62 Shenjhong Road, Yanchao District, Kaohsiung 82444, Taiwan.
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Ascensao JA, Datta P, Hancioglu B, Sontag E, Gennaro ML, Igoshin OA. Non-monotonic Response to Monotonic Stimulus: Regulation of Glyoxylate Shunt Gene-Expression Dynamics in Mycobacterium tuberculosis. PLoS Comput Biol 2016; 12:e1004741. [PMID: 26900694 PMCID: PMC4762938 DOI: 10.1371/journal.pcbi.1004741] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 01/07/2016] [Indexed: 01/27/2023] Open
Abstract
Understanding how dynamical responses of biological networks are constrained by underlying network topology is one of the fundamental goals of systems biology. Here we employ monotone systems theory to formulate a theorem stating necessary conditions for non-monotonic time-response of a biochemical network to a monotonic stimulus. We apply this theorem to analyze the non-monotonic dynamics of the σB-regulated glyoxylate shunt gene expression in Mycobacterium tuberculosis cells exposed to hypoxia. We first demonstrate that the known network structure is inconsistent with observed dynamics. To resolve this inconsistency we employ the formulated theorem, modeling simulations and optimization along with follow-up dynamic experimental measurements. We show a requirement for post-translational modulation of σB activity in order to reconcile the network dynamics with its topology. The results of this analysis make testable experimental predictions and demonstrate wider applicability of the developed methodology to a wide class of biological systems.
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Affiliation(s)
- Joao A. Ascensao
- Department of Bioengineering and Center for Theoretical Biological Physics, Rice University, Houston, Texas, United States of America
| | - Pratik Datta
- Public Health Research Institute, New Jersey Medical School, Rutgers University, Newark, New Jersey, United States of America
| | - Baris Hancioglu
- Department of Bioengineering and Center for Theoretical Biological Physics, Rice University, Houston, Texas, United States of America
| | - Eduardo Sontag
- Department of Mathematics and Center for Quantitative Biology, Rutgers University, Piscataway, New Jersey, United States of America
| | - Maria L. Gennaro
- Public Health Research Institute, New Jersey Medical School, Rutgers University, Newark, New Jersey, United States of America
| | - Oleg A. Igoshin
- Department of Bioengineering and Center for Theoretical Biological Physics, Rice University, Houston, Texas, United States of America
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van der Steen JB, Hellingwerf KJ. Activation of the General Stress Response of Bacillus subtilis by Visible Light. Photochem Photobiol 2015; 91:1032-45. [PMID: 26189730 DOI: 10.1111/php.12499] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2015] [Accepted: 06/25/2015] [Indexed: 12/20/2022]
Abstract
A key challenge for microbiology is to understand how evolution has shaped the wiring of regulatory networks. This is amplified by the paucity of information of power-spectra of physicochemical stimuli to which microorganisms are exposed. Future studies of genome evolution, driven by altered stimulus regimes, will therefore require a versatile signal transduction system that allows accurate signal dosing. Here, we review the general stress response of Bacillus subtilis, and its upstream signal transduction network, as a candidate system. It can be activated by red and blue light, and by many additional stimuli. Signal integration therefore is an intricate function of this system. The blue-light response is elicited via the photoreceptor YtvA, which forms an integral part of stressosomes, to activate expression of the stress regulon of B. subtilis. Signal transfer through this network can be assayed with reporter enzymes, while intermediate steps can be studied with live-cell imaging of fluorescently tagged proteins. Different parts of this system have been studied in vitro, such that its computational modeling has made significant progress. One can directly relate the microscopic characteristics of YtvA with activation of the general stress regulon, making this system a very well-suited system for network evolution studies.
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Affiliation(s)
- Jeroen B van der Steen
- Molecular Microbial Physiology Group, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Klaas J Hellingwerf
- Molecular Microbial Physiology Group, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
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Hou XH, Zhang JQ, Song XY, Ma XB, Zhang SY. Contribution of ClpP to stress tolerance and virulence properties of Streptococcus mutans. J Basic Microbiol 2014; 54:1222-32. [PMID: 24979467 DOI: 10.1002/jobm.201300747] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 03/18/2014] [Indexed: 11/06/2022]
Abstract
Abilities to tolerate environmental stresses and to form biofilms on teeth surface are key virulence attributes of Streptococcus mutans, the primary causative agent of human dental caries. ClpP, the chief intracellular protease of S. mutans, along with ATPases degrades altered proteins that might be toxic for bacteria, and thus plays important roles in stress response. To further understand the roles of ClpP in stress response of S. mutans, a ClpP deficient strain was constructed and used for general stress tolerance, autolysis, mutacins production, and virulence assays. Here, we demonstrated that inactivation of ClpP in S. mutans resulted in a sensitive phenotype to several environmental stresses, including acid, cold, thermal, and oxidative stresses. The ClpP deficient strain displayed slow growth rates, poor growth yields, formation of long chains, increased clumping in broth, and reduced capacity to form biofilms in presence of glucose. Mutacins production and autolysis of S. mutans were also impaired by mutation of clpP. Animals study showed that clpP mutation increased virulence of S. mutans but not significant. However, enhanced abilities to survive lethal acid and to form biofilm in sucrose were observed in ClpP deficient strain. Our findings revealed a broad impact of ClpP on several virulence properties of S. mutans and highlighted the relevance of ClpP proteolysis with progression of diseases caused by S. mutans.
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Affiliation(s)
- Xiang-Hua Hou
- Department of Clinical Laboratory, The First Affiliated Hospital of Xiamen University, Xiamen, China
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Identification of genes transcribed by Streptococcus equi ssp. zooepidemicus in infected porcine lung. Microb Pathog 2013; 59-60:7-12. [DOI: 10.1016/j.micpath.2013.02.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Revised: 01/31/2013] [Accepted: 02/04/2013] [Indexed: 01/03/2023]
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Michalik S, Bernhardt J, Otto A, Moche M, Becher D, Meyer H, Lalk M, Schurmann C, Schlüter R, Kock H, Gerth U, Hecker M. Life and death of proteins: a case study of glucose-starved Staphylococcus aureus. Mol Cell Proteomics 2012; 11:558-70. [PMID: 22556279 DOI: 10.1074/mcp.m112.017004] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The cellular amount of proteins not only depends on synthesis but also on degradation. Here, we expand the understanding of differential protein levels by complementing synthesis data with a proteome-wide, mass spectrometry-based stable isotope labeling with amino acids in cell culture analysis of protein degradation in the human pathogen Staphylococcus aureus during glucose starvation. Monitoring protein stability profiles in a wild type and an isogenic clpP protease mutant revealed that 1) proteolysis mainly affected proteins with vegetative functions, anabolic and selected catabolic enzymes, whereas the expression of TCA cycle and gluconeogenesis enzymes increased; 2) most proteins were prone to aggregation in the clpP mutant; 3) the absence of ClpP correlated with protein denaturation and oxidative stress responses, deregulation of virulence factors and a CodY repression. We suggest that degradation of redundant, inactive proteins disintegrated from functional complexes and thereby amenable to proteolytic attack is a fundamental cellular process in all organisms to regain nutrients and guarantee protein homeostasis.
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Affiliation(s)
- Stephan Michalik
- Institute of Microbiology, Ernst-Moritz-Arndt University, Greifswald, Germany
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Liebal UW, Sappa PK, Millat T, Steil L, Homuth G, Völker U, Wolkenhauer O. Proteolysis of beta-galactosidase following SigmaB activation in Bacillus subtilis. MOLECULAR BIOSYSTEMS 2012; 8:1806-14. [DOI: 10.1039/c2mb25031d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Stressosomes formed in Bacillus subtilis from the RsbR protein of Listeria monocytogenes allow σ(B) activation following exposure to either physical or nutritional stress. J Bacteriol 2010; 192:6279-86. [PMID: 20935101 DOI: 10.1128/jb.00467-10] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The general stress regulon of Bacillus subtilis is controlled by σ(B), a transcription factor that is activated by physical or nutritional stress. In B. subtilis, each of these two stresses is communicated to the primary σ(B) regulators by distinct pathways. Physical stress activation of σ(B) involves a large-molecular-mass (>10(6)-Da) structure (stressosome) formed by one or more homologous proteins (RsbRA, -B, -C, and -D) onto which the pathway's principal regulators are bound. The RsbR proteins are thought to be potential receptors for stress signaling. Listeria monocytogenes encodes orthologs of σ(B) and its principal regulators; however, unlike B. subtilis, L. monocytogenes appears to use the stressosome pathway for both physical and nutritional stress activation of σ(B). In the current work, a B. subtilis strain that expressed L. monocytogenes rsbR (rsbR(Lm)) in lieu of B. subtilis rsbR (rsbR(Bs)) was created and was found to display the Listeria phenotype of σ(B) activation following exposure to either physical or nutritional stress. B. subtilis expressing either the RsbR paralog rsbRC or rsbRD, but not rsbRA or rsbRB, as the sole source of RsbR also allowed σ(B) induction following nutritional stress. It is unclear whether the nutritional stress induction seen in these strains is the result of a direct effect of nutritional stress on stressosome activity or a consequence of the background levels of σ(B) activation in these strains and the effects of diminished ATP on the downstream phosphorylation reaction needed to reinactivate σ(B).
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Reeves A, Martinez L, Haldenwang W. Expression of, and in vivo stressosome formation by, single members of the RsbR protein family in Bacillus subtilis. MICROBIOLOGY-SGM 2009; 156:990-998. [PMID: 20019076 DOI: 10.1099/mic.0.036095-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The Bacillus subtilis stressosome is a 1.8 MDa complex that is the focal point for activating the bacterium's general response to physical stress. In vitro studies demonstrated that the stressosome's core element can be formed from one or more of a family of paralogous proteins (RsbRA, -RB, -RC and -RD) onto which the system's activator protein (RsbT) and its principal inhibitor (RsbS) are bound. The RsbR components of the stressosome are envisioned to be the initial receptors of stress signalling with the stressosome structure itself serving as a device to integrate multiple stress signals for a coordinated response. In the current work, we examine several of the in vivo characteristics of the RsbR family members, including their expression and ability to form stressosomes to regulate sigma(B). Translational fusions of lacZ to each rsbR paralogue revealed that rsbRA, -RB and -RC are expressed at similar levels, which remain relatively constant during growth, ethanol stress and entry into stationary phase. rsbRD, in contrast, is expressed at a level that is only slightly above background during growth, but is induced to 30 % of the rsbRA expression level following ethanol stress. Velocity sedimentation analyses of B. subtilis extracts from strains expressing single rsbR paralogues demonstrated that each incorporates RsbS into fast-sedimenting complexes. However, consistent with rsbRD's lower expression, the RsbRD-dependent RsbS complexes were present at only 20 % of the level of the complexes seen in a wild-type strain. The lower stressosome level in the RsbRD strain is still able to hold RsbT's activity in check, implying that the RsbR/S component of stressosomes is normally in excess for the control of RsbT. Consistent with such a notion, reporter gene and Western blot assays demonstrate that although RsbT is synthesized at the same rate as RsbRA and RsbS, RsbT's ultimate level in growing B. subtilis is only 10 % that of RsbRA. Apparently, RsbT's inherent structure and/or its passage between the stressosome and its activation target compromises its persistence.
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Affiliation(s)
- Adam Reeves
- Department of Microbiology and Immunology, The University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA
| | - Luis Martinez
- Department of Microbiology and Immunology, The University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA
| | - William Haldenwang
- Department of Microbiology and Immunology, The University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA
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Kayumov A, Heinrich A, Sharipova M, Iljinskaya O, Forchhammer K. Inactivation of the general transcription factor TnrA in Bacillus subtilis by proteolysis. MICROBIOLOGY-SGM 2008; 154:2348-2355. [PMID: 18667567 DOI: 10.1099/mic.0.2008/019802-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Under conditions of nitrogen limitation, the general transcription factor TnrA in Bacillus subtilis activates the expression of genes involved in assimilation of various nitrogen sources. Previously, TnrA activity has been shown to be controlled by protein-protein interaction with glutamine synthetase, the key enzyme of ammonia assimilation. Furthermore, depending on ATP and 2-oxoglutarate levels, TnrA can bind to the GlnK-AmtB complex. Here, we report that upon transfer of nitrate-grown cells to combined nitrogen-depleted medium, TnrA is rapidly eliminated from the cells by proteolysis. As long as TnrA is membrane-bound through GlnK-AmtB interaction it seems to be protected from degradation. Upon removal of nitrogen sources, the localization of TnrA becomes cytosolic and degradation occurs. The proteolytic activity against TnrA was detected in the cytosolic fraction but not in the membrane, and its presence does not depend on the nitrogen regime of cell growth. The proteolytic degradation of TnrA as a response to complete nitrogen starvation might represent a novel mechanism of TnrA control in B. subtilis.
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Affiliation(s)
- Airat Kayumov
- Department of Microbiology, Kazan State University, Kremlevskaya 18, 420008 Kazan, Russia
| | - Annette Heinrich
- Institut für Mikrobiologie, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 28, D-72076 Tübingen, Germany
| | - Margarita Sharipova
- Department of Microbiology, Kazan State University, Kremlevskaya 18, 420008 Kazan, Russia
| | - Olga Iljinskaya
- Department of Microbiology, Kazan State University, Kremlevskaya 18, 420008 Kazan, Russia
| | - Karl Forchhammer
- Institut für Mikrobiologie, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 28, D-72076 Tübingen, Germany
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Marles-Wright J, Lewis RJ. Stress responses of bacteria. Curr Opin Struct Biol 2007; 17:755-60. [DOI: 10.1016/j.sbi.2007.08.004] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2007] [Revised: 07/31/2007] [Accepted: 08/01/2007] [Indexed: 10/22/2022]
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