Nucleotide sequence of the glyceraldehyde-3-phosphate dehydrogenase gene from the mesophilic methanogenic archaebacteria Methanobacterium bryantii and Methanobacterium formicicum. Comparison with the respective gene structure of the closely related extreme thermophile Methanothermus fervidus.

摘要: The genes for glyceraldehyde-3-phosphate dehydrogenase (gap genes) from the mesophilic methanogenic archaebacteria Methanobacterium formicicum and bryantii were cloned sequenced. deduced amino acid sequences show 95% identity to each other about 70% thermophilic archaebacterium Methanothermus fervidus. Although sequence similarity between archaebacterial homologous enzyme of eubacteria eukaryotes is low, an equivalent secondary-structural arrangement can be profiles physical parameters hydropathy, chain flexibility amphipathy. In order find possible thermophile-specific structural features M. fervidus, a comparative primary-sequence analysis was performed. Amino exchanges leading, stabilization main-chain conformation, could found throughout thermophile enzyme. Striking are preference isoleucine, especially in β-sheets, low arginine/lysine ratio 0.54.