NMR structure determination and structure-based functional characterization of conserved hypothetical protein MTH1175 from Methanobacterium thermoautotrophicum.

J R Cort; A Yee; A M Edwards; C H Arrowsmith; M A Kennedy

doi:10.1023/a:1011348803324

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NMR structure determination and structure-based functional characterization of conserved hypothetical protein MTH1175 from Methanobacterium thermoautotrophicum.

J R Cort·A Yee·A M Edwards·C H Arrowsmith·M A Kennedy

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Abstract

The solution structure of MTH1175, a 124-residue protein from the archaeon Methanobacterium thermoautotrophicum has been determined by NMR spectroscopy. MTH1175 is part of a family of conserved hypothetical proteins (COG1433) with unknown functions which contains multiple paralogs from all complete archaeal genomes and the archaeal gene-rich bacterium Thermotoga maritima. Sequence similarity indicates this protein family may be related to the nitrogen fixation proteins NifB and NifX. MTH1175 adopts an alpha/beta topology with a single mixed beta-sheet, and contains two flexible loops and an unstructured C-terminal tail. The fold resembles that of Ribonuclease H and similar proteins, but differs from these in several respects, and is not likely to have a nuclease activity.

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Amino Acid Sequence Archaeal Proteins Cloning, Molecular Conserved Sequence Magnetic Resonance Spectroscopy Methanobacterium Models, Molecular Molecular Sequence Data Protein Conformation Protein Structure, Secondary Recombinant Proteins Sequence Alignment Sequence Homology, Amino Acid Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.

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J R Cort, A Yee, A M Edwards, C H Arrowsmith, M A Kennedy. 2000. NMR structure determination and structure-based functional characterization of conserved hypothetical protein MTH1175 from Methanobacterium thermoautotrophicum.. https://doi.org/10.1023/a%3A1011348803324

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