UV-B Radiation Stress Causes Alterations in Whole Cell Protein Profile and Expression of Certain Genes in the Rice Phyllospheric Bacterium Enterobacter cloacae.
Among the different types of UV radiation, UV-B radiation (280-315 nm) has gained much attention mainly due to its increasing incidence on the Earth's surface leading to imbalances in natural ecosystems. This study deals with the effects of UV-B radiation on the proteome and gene expression in a rice phyllospheric bacterium, Enterobacter cloacae. Of the five bacteria isolated from rice leaves, E. cloacae showed the highest level of resistance to UV-B and total killing occurred after 8 h of continuous exposure to UV-B. Reactive oxygen species were induced by UV-B exposure and increased with increasing duration of exposure. Protein profiling by SDS-PAGE and 2-dimensional gel electrophoresis (2-DE) revealed major changes in the number as well as expression of proteins. Analysis of 2-DE gel spots indicated up/down-regulation of several proteins under the stress of UV-B radiation. Thirteen differentially expressed proteins including two hypothetical proteins were identified by MALDI-TOF MS and assigned to eight functional categories. Both the hypothetical proteins (gi 779821175 and gi 503938301) were over-expressed after UV-B irradiation; gi 503938301 was characterized as a member of FMN reductase superfamily whereas gi 779821175 seems to be a structural protein as it did not show any functional domain. That the expression of certain proteins under UV-B stress is indeed up-regulated was confirmed by qRT-PCR. Transcript analysis of selected gene including genes of hypothetical proteins (cp011650 and cp002886) showed over-expression under UV-B stress as compared to untreated control cultures. Although this study deals with a limited number of proteins, identification of differentially expressed proteins reported herein may prove useful in future studies especially for assessing their significance in the protection mechanism of bacteria against UV-B radiation stress.
School of Biotechnology, Institute of Science, Banaras Hindu University Varanasi, India.
Jay
J
Kumar
School of Biotechnology, Institute of Science, Banaras Hindu University Varanasi, India.
Piyoosh K
PK
Babele
School of Biotechnology, Institute of Science, Banaras Hindu University Varanasi, India.
Divya
D
Singh
School of Biotechnology, Institute of Science, Banaras Hindu University Varanasi, India.
Ashok
A
Kumar
2-D gel electrophoresis; UV-B radiation; gene expression; phyllospheric bacteria; proteome
Arch Biochem Biophys. 1997 Jan 1;337(1):89-95
8990272
J Photochem Photobiol B. 2012 Dec 5;117:40-6
23026387
Proteomics. 2002 Sep;2(9):1325-46
12362351
Nat Protoc. 2006;1(6):2856-60
17406544
J Proteomics. 2014 Jan 16;96:271-90
24291601
Indian J Microbiol. 2012 Dec;52(4):660-5
24293727
Methods. 2001 Dec;25(4):402-8
11846609
Ecol Lett. 2007 Apr;10(4):332-45
17355571
Lett Appl Microbiol. 2007 May;44(5):513-9
17451518
Environ Microbiol. 2013 Apr;15(4):991-1000
22712445
Electrophoresis. 2004 May;25(9):1327-33
15174055
Microb Ecol. 2005 Jan;49(1):104-13
15883865
Structure. 1995 Dec 15;3(12):1367-77
8747463
J Biol Chem. 1997 Jun 20;272(25):15607-12
9188448
J Nucleic Acids. 2010 Dec 16;2010:592980
21209706
Appl Environ Microbiol. 2001 Dec;67(12):5488-96
11722897
Environ Microbiol. 1999 Feb;1(1):75-87
11207720
PLoS One. 2014 May 19;9(5):e98162
24841066
Front Microbiol. 2015 Apr 22;6:328
25954258
Carlsberg Res Commun. 1988;53(6):357-70
3076376
Photochem Photobiol Sci. 2007 Mar;6(3):267-85
17344962
Antioxid Redox Signal. 2011 Aug 1;15(3):781-94
20919930
Int J Low Extrem Wounds. 2009 Dec;8(4):203-8
19934183
Environ Sci Technol. 2013 Jun 18;47(12):6306-15
23692317
J Photochem Photobiol B. 1998 Oct;46(1-3):5-19
9894350
Biochem Biophys Res Commun. 2010 Jul 2;397(3):603-7
20570649
J Bacteriol. 2005 May;187(10):3556-64
15866945
Nat Rev Microbiol. 2012 Dec;10(12):828-40
23154261
Appl Environ Microbiol. 2003 Apr;69(4):1875-83
12676659
Proteomics. 2006 Jun;6(12):3614-24
16691555
J Biol Chem. 2002 Mar 15;277(11):8949-54
11777918
Anal Biochem. 1976 May 7;72:248-54
942051
BMC Res Notes. 2010 Aug 16;3:226
20712861
Environ Microbiol. 2009 Oct;11(10):2660-75
19601963
Front Microbiol. 2015 Feb 24;6:133
25759687
Environ Pollut. 2016 Jan;208(Pt B):626-36
26552525
Microb Ecol. 2003 May;45(4):353-61
12704563
J Bacteriol. 2012 Dec;194(24):6928-9
23209197
Photochem Photobiol Sci. 2013 Feb;12(2):262-71
22972197
Bioinformatics. 2007 Nov 1;23(21):2947-8
17846036