Romesser J A, Wolfe R S
Biochem J. 1981 Sep 1;197(3):565-71. doi: 10.1042/bj1970565.
Chemical reaction of coenzyme M, sodium 2-mercaptoethanesulphonate (HS-CoM, Na+), and formaldehyde formed sodium 2-(hydroxymethylthio)ethanesulphonate (HOCH2-S-CoM), whereas reaction with the ammonium salt of HS-CoM yielded iminobis-[2-(methylthio)ethanesulphonate], monoammonium salt [NH = (CH2 - S - CoM)2]. In water, NH = (CH2 - S - CoM)2 decomposed to 2-(aminomethylthio)ethanesulphonate (NH2CH2 - S - CoM) and HOCH2-S-CoM. NH-2-CH2 - CoM was degraded further to form more HOCH2-S-CoM. The structures of these coenzyme M derivatives were confirmed by i.r. and n.m.r. spectroscopy and by elemental analysis. When added to cell extracts of Methanobacterium thermoautotrophicum, methane was formed from either HOCH2 - S - CoM or NH = (CH2 - S - CoM)2 at rates comparable with the rate of methane formation from the methanogenic precursor 2-(methylthio)-ethanesulphonate (CH3 - S - CoM). Formaldehyde was reduced to methane at similar rates. In addition, certain hemimercaptals, including thiazolidine and thiazolidine-4-carboxylate, were reduced, although at slower rates. The reduction of formaldehyde, thiazolidine, or thiazolidine-4-carboxylate required catalytic amounts of HS-CoM. ATP was required by cells extracts for reduction of each of these methane precursors.
辅酶M（2-巯基乙烷磺酸钠，HS-CoM，Na⁺）与甲醛发生化学反应生成2-（羟甲基硫代）乙烷磺酸钠（HOCH₂-S-CoM），而与HS-CoM的铵盐反应则生成亚氨基双[2-（甲硫基）乙烷磺酸盐]单铵盐[NH = (CH₂ - S - CoM)₂]。在水中，NH = (CH₂ - S - CoM)₂分解为2-（氨甲基硫代）乙烷磺酸盐（NH₂CH₂ - S - CoM）和HOCH₂-S-CoM。NH₂CH₂ - CoM进一步降解形成更多的HOCH₂-S-CoM。这些辅酶M衍生物的结构通过红外光谱、核磁共振光谱和元素分析得以确证。当添加到嗜热自养甲烷杆菌的细胞提取物中时，HOCH₂ - S - CoM或NH = (CH₂ - S - CoM)₂均可生成甲烷，其生成速率与产甲烷前体2-（甲硫基）乙烷磺酸盐（CH₃ - S - CoM）生成甲烷的速率相当。甲醛以相似的速率被还原为甲烷。此外，某些半硫醛，包括噻唑烷和噻唑烷-4-羧酸盐，也能被还原，不过速率较慢。甲醛、噻唑烷或噻唑烷-4-羧酸盐的还原需要催化量的HS-CoM。细胞提取物还原这些甲烷前体中的每一种都需要ATP。
