Goodchild Amber, Saunders Neil F W, Ertan Haluk, Raftery Mark, Guilhaus Michael, Curmi Paul M G, Cavicchioli Ricardo
School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, 2052, NSW, Australia.
Mol Microbiol. 2004 Jul;53(1):309-21. doi: 10.1111/j.1365-2958.2004.04130.x.
A global view of the biology of the cold-adapted archaeon Methanococcoides burtonii was achieved using proteomics. Proteins specific to growth at 4 degrees C versus T(opt) (23 degrees C) were identified by mass spectrometry using the draft genome sequence of M. burtonii. mRNA levels were determined for all genes identified by proteomics, and specific enzyme assays confirmed the protein expression results. Key aspects of cold adaptation related to transcription, protein folding and metabolism, including specific roles for RNA polymerase subunit E, a response regulator and peptidyl prolyl cis/trans isomerase. Heat shock protein DnaK was expressed during growth at T(opt), indicating that growth at 'optimal' temperatures was stressful for this cold-adapted organism. Expression of trimethylamine methyltransferase involves contiguous translation of two open reading frames, which is likely to result from incorporation of pyrrolysine at an amber stop codon. Thermal regulation in M. burtonii is achieved through complex gene expression events involving gene clusters and operons, through to protein modifications.
通过蛋白质组学对嗜冷古菌伯氏甲烷球形菌的生物学特性有了全面的认识。利用伯氏甲烷球形菌的基因组草图序列，通过质谱法鉴定了在4℃与最适温度（23℃）下生长的特异性蛋白质。对蛋白质组学鉴定出的所有基因测定了mRNA水平，特定的酶活性测定证实了蛋白质表达结果。冷适应的关键方面涉及转录、蛋白质折叠和代谢，包括RNA聚合酶亚基E、一种应答调节因子和肽基脯氨酰顺/反异构酶的特定作用。热休克蛋白DnaK在最适温度下生长时表达，表明在“最适”温度下生长对这种嗜冷生物来说是有压力的。三甲胺甲基转移酶的表达涉及两个开放阅读框的连续翻译，这可能是由于在琥珀色终止密码子处掺入了吡咯赖氨酸所致。伯氏甲烷球形菌的热调节是通过涉及基因簇和操纵子的复杂基因表达事件直至蛋白质修饰来实现的。
