南极菌Pseudoalteromonas sp.S-15-13引导糖基转移酶基因表达对环境因子变化的响应
Effects of environmental factors on the pGTF gene expression of Antarctic bacterium Pseudoalteromonas sp.S-15-13
-
摘要: 为了探讨胞外多糖在南极微生物低温适应性中的作用与机制,克隆了南极菌Pseudoalteromonas sp.S-15-13的引导糖基转移酶(GTF)核心片段,并采用Real-Time PCR的方法研究了温度、冻融循环、盐浓度、pH等条件对该糖基转移酶基因(gtf)表达的影响。结果表明,低温有利于gtf的表达,短时的低温刺激(2℃)1 h后,gtf的表达量即上调为对照的1.5倍;而该菌经4和10℃培养24 h后gtf的表达量约为20℃时的8~12倍;经过冻融循环gtf的表达量上调,在第2个冻融循环后gtf 的表达量较对照提高了3.667倍;盐浓度对gtf的影响表现为低促高抑,即NaCl含量为6.0 %时gtf 的表达量是对照(3.0%)的3.59倍,当NaCl含量达9.0 %时gtf 表达量则显著下调;在一定范围内(pH5.0~8.0),pH的改变会促进gtf 的表达,当pH为6.0时gtf 表达量约为pH7.0时的2倍。该结果为探讨胞外多糖在南极微生物环境适应性中的作用与机制提供了科学依据。
-
关键词:
- 南极菌Pseudoalteromonassp.S-15-13 /
- 糖基转移酶 /
- Real-timePCR /
- 环境因子
Abstract: The priming glycosyltransferase gene (gtf) was cloned from the Antarctic bacterium Pseudoalteromonas sp.S-15-13,which was isolated from sea ice (62°00'S,68°30'E) samples,in order to explore the role and mechanism of extracellular polysaccharides on the low temperature adaptation of this strain.The effects of environmental factors (such as temperature, treatment with freeze-thaw cycles, salt concentrations and pH values) on gtf expression were studied with real-time PCR techniques.It was shown that the gtf expression level of S-15-13 stimulation at 2℃ was about 1.5 times that grown at 10℃ after 1h; and the gtf expression level of S-15-13 grown at 4 and 10℃ was about 8~12 times that grown at 20℃ after 24 h culture; the expression level of gtf was 3.667 times higher than the untreated sample after two freeze-thaw cycles of Pseudoalteromonas sp.S-15-13; 6.0% NaCl could increase the expression level of gtf nearly four times compared to that of 3.0% NaCl, but when the NaCl concentration reached 9.0 %, the expression level of gtf dropped off sharply; pH changes in the range of pH 5.0~8.0 could promote the expression of gtf: the level of gtf expression at pH 6.0 was 2 times that at pH 7.0.Study on gtf of Pseudoalteromonas sp.S-15-13 may have potential to deepen our understanding of the adaptation mechanism of Antarctic bacteria living in harsh environments. -
曾胤新, 陈波.南极低温微生物研究及应用前景[J].极地研究, 1999, 11(2): 143-152. KIRST G,WIENCKE C.Ecophysiology of polaralgae[J].J Phyco1, 1995, 31:181-199. RUSSEL N J.Psychrophilic bacteria-molecular adaptations of membmne lipids[J].Comp Biochem Physio1 A Physio, 1997, 11(3): 489-493. SELBMANN L, ONOFRI S, FENICE M, et a1.Production and structural characterization of the exopolysaccharide of the Antarctic fungus Phoma herbarum CCFEE 5080 [J].Research in Microbiology, 2002, 153(9): 585-592. KREMBS C,ENGEL A.Abundance and variability of microorganisms and transparent exopolymer particles across ice-water interface of melting firstyear sea ice in t he Laptev Sea (Arctic) [J].Mar Biol,200,138: 173-185. KREMBS C,EICKEN H,JUNGE K,et al.High concentrations of exopolymeric substances in Arctic winter sea ice: Implications for the polar ocean carbon cycle and cryoprotection of diatoms[J].Deep-Sea Res,2002,49: 2163-2181. MORONA J K, MORONA R, PATON J C.Characterization of the locus encoding the Streptomyces pneumoniae type19F capsular polysaccharide biosynthetic pathway[J].Mol Microbiol,1997,23: 751-763. WHITFIELD C, VALVANO M A.Biosynthesis and expression of cell-surface polysaccharides in Gram-negative bacterial[J].Adv Microbial Physiol,1993,35: 136-246. BAI L P,JIANG R, SHAN J J,et al.Purification, characterization and functional analysis of asparagines synthetase encoding by ste10 gene in Ebosin biosynthesis of Streptomyces sp.139[J].Enzyme and Microbial Technology,2008, 42: 548-553. JOLLY L,STINGELE F.Molecular organization and functionality of exopolysaccharide gene clusters in lactic acid bacteria[J].International Dairy Journal, 2001,11: 733-745. THOMAS D N, DIECKMANN G S.Antarctic sea ice a habitat for extremophiles[J].Science, 2002,295(25): 641-644. WHITFIELD C,AMOR P A,KOPLIN R.Modulation of the surface architecture Gram-negative bacteria by the action of surface Polymer: lipid A-core ligase and by determinants of polymer chain length[J].Mol Microbiol, 1997, 23: 629-638. MANCUSO N C, GARON S, BOWMAN J P, et al.Production of exopolysaccharides by Antarctic marine bacterial isolates[J].J Appl Microbiol, 2004, 96: 1057-1066. 李江,何培青,陈靠山,等.南极适冷菌 Pseudoalteromonas sp.S-15-13胞外多糖低温保护作用的研究[J].海洋科学进展,2007, 25(2):215-219. SULLIVAN C W,PALMISANO A C.Sea ice microbial communities: distribution, abundance and diversity of ice bacteria in McMurdo Sound, Antarctica, in 1980[J].Appl Environ Microbiol, 1984,47: 788-795.
点击查看大图
计量
- 文章访问数: 1249
- HTML全文浏览量: 4
- PDF下载量: 841
- 被引次数: 0