Mueller Eugene G
Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA.
Nat Chem Biol. 2006 Apr;2(4):185-94. doi: 10.1038/nchembio779.
The presence of sulfur in cofactors has been appreciated for over a century, but the trafficking and delivery of sulfur to cofactors and nucleosides is still not fully understood. In the last decade, great strides have been made toward understanding those processes and the enzymes that conduct them, including cysteine desulfurases and rhodanese homology domain proteins. The persulfide group (R-S-SH) predominantly serves as the sulfur donor, and sulfur incorporation pathways share enzymes to a remarkable degree. Mechanisms for the use of persulfide groups are illustrated with the relatively simple case of 4-thiourdine generation, and further possibilities are illuminated by the 2-thiouridine and cofactor biosynthetic systems. The rationale and ramifications of sharing enzymes between sulfur incorporation pathways are discussed, including implications for interpreting genetic or genomic data that indicate a role for a sulfur transfer protein in a particular biological process.
辅因子中硫的存在已被认识一个多世纪了，但硫向辅因子和核苷的运输及传递仍未被完全理解。在过去十年中，在理解这些过程以及执行这些过程的酶方面取得了巨大进展，包括半胱氨酸脱硫酶和硫氧还蛋白同源结构域蛋白。过硫化物基团（R-S-SH）主要作为硫供体，并且硫掺入途径在很大程度上共享酶。以相对简单的4-硫尿苷生成情况为例说明了过硫化物基团的使用机制，2-硫尿苷和辅因子生物合成系统则揭示了更多可能性。讨论了硫掺入途径之间共享酶的基本原理和影响，包括对解释表明硫转移蛋白在特定生物学过程中起作用的遗传或基因组数据的影响。
