作者:Carole L Linster、Emile Van Schaftingen、Andrew D Hanson
DOI:10.1038/nchembio.1141
日期:2013.2
Metabolites and cofactors can be converted to unwanted compounds by promiscuous enzymes and spontaneous chemical reactions. The growing list of enzymes that correct or prevent these reactions, akin to those that combat DNA and protein damage, have important roles in maintaining homeostasis and preventing disease. It is increasingly evident that metabolites suffer various kinds of damage, that such damage happens in all organisms and that cells have dedicated systems for damage repair and containment. First, chemical biology is demonstrating that diverse metabolites are damaged by side reactions of 'promiscuous' enzymes or by spontaneous chemical reactions, that the products are useless or toxic and that the unchecked buildup of these products can be devastating. Second, genetic and genomic evidence from prokaryotes and eukaryotes is implicating a network of new, conserved enzymes that repair damaged metabolites or somehow pre-empt damage. Metabolite (that is, small-molecule) repair is analogous to macromolecule (DNA and protein) repair and seems from comparative genomic evidence to be equally widespread. Comparative genomics also implies that metabolite repair could be the function of many conserved protein families lacking known activities. Howâand how wellâcells deal with metabolite damage affects fields ranging from medical genetics to metabolic engineering.
代谢物和辅助因子可通过杂乱的酶和自发的化学反应转化为不需要的化合物。纠正或防止这些反应的酶越来越多,它们与防止 DNA 和蛋白质损伤的酶类似,在维持体内平衡和预防疾病方面发挥着重要作用。 越来越多的事实证明,代谢物会受到各种损伤,所有生物体都会发生这种损伤,而且细胞有专门的损伤修复和抑制系统。首先,化学生物学证明,各种代谢物会因 "杂乱 "酶的副反应或自发化学反应而受损,其产物是无用的或有毒的,这些产物的无节制积累会造成毁灭性后果。其次,来自原核生物和真核生物的基因和基因组证据表明,有一种新的、保守的酶网络可以修复受损的代谢物,或以某种方式预先防止损害。代谢物(即小分子)修复类似于大分子(DNA 和蛋白质)修复,从比较基因组学证据来看,似乎同样普遍。比较基因组学还表明,代谢物修复可能是许多缺乏已知活性的保守蛋白家族的功能。细胞如何以及如何很好地处理代谢物损伤影响着从医学遗传学到代谢工程等各个领域。