High impact information on methanopterin

• Carbon dioxide reduction factor and methanopterin, two coenzymes required for CO2 reduction to methane by extracts of Methanobacterium [1].
• Genetic analysis of mch mutants in two Methanosarcina species demonstrates multiple roles for the methanopterin-dependent C-1 oxidation/reduction pathway and differences in H(2) metabolism between closely related species [2].
• This pathway for the biosynthesis of methanopterin represents the first example of the modification of the specificity of a coenzyme through a methylation reaction [3].
• Methanofuran (carbon dioxide reduction factor) became labeled when incubated in cell extracts of Methanobacterium under hydrogen and 14CO2 in the absence of methanopterin [4].
• In this article we analyse the SSM for the presence of methanopterin-linked C1 transfer genes that are signature for methylotrophy [5].

Biological context of methanopterin

• Fishing for biodiversity: novel methanopterin-linked C transfer genes deduced from the Sargasso Sea metagenome [5].
• Acid hydrolysis of methanopterin cleaved the 5'----1'' glycosidic bond and yielded a 'hydrolytic product' which was identified as N-[1'-(2''-amino-4''-hydroxy-7'' -methyl-6''-pteridinyl)ethyl]-4-[2', 3', 4', 5'-tetrahydroxypent-1'-yl]aniline [6].

Associations of methanopterin with other chemical compounds

• Structural elements of methanopterin, a novel pterin present in Methanobacterium thermoautotrophicum [7].
• Independent of the physiological condition of Methanobacterium thermoautotrophicum methanopterin was formed upon O2 exposure [8].
• Methanosarcina barkeri contains a closely related coenzyme called sarcinapterin, which was identified as a L-glutamyl derivative of methanopterin, where the glutamate moiety is attached to the alpha-carboxylic acid group of the alpha-hydroxyglutaric acid moiety of methanopterin via an amide linkage [6].
• Extracts of Methanospirillum hungatei, Methanobrevibacter smithii and Methanoplanus endosymbiosus were found to contain 7-methylpterin and methanopterin [9].

Gene context of methanopterin

• In general, all methanogens were found to contain coenzyme F420 analogues, methanopterin (MPT) analogues and 5-hydroxybenzimidazolylcobamide (vitamin B12-HBI) [10].
• An unidentified methanopterin-like compound was detected in extracts of these two species and of Msp. hungatei, while a 7-methylpterin-like compound was found in extracts of Mp. endosymbiosus [9].
• Formyl-FAF or formyl-methanopterin (YFC, a very rapidly labelled compound during 14C pulse labeling) has been implicated as an obligate intermediate in methanogenesis, since methanopterin or FAF is an essential component of the carbon dioxide reducing factor in dialyzed extract methanogenesis [11].

References