Mayer Jutta, Denger Karin, Smits Theo H M, Hollemeyer Klaus, Groth Ulrich, Cook Alasdair M
Fachbereich Biologie der Universität Konstanz, 78457 Konstanz, Germany.
Arch Microbiol. 2006 Jul;186(1):61-7. doi: 10.1007/s00203-006-0123-7. Epub 2006 Jun 21.
The naturally occurring sulfonate N-acetyltaurine was synthesized chemically and its identity was confirmed. Aerobic enrichment cultures for bacteria able to utilize N-acetyltaurine as sole source of fixed nitrogen or as sole source of carbon were successful. One representative isolate, strain NAT, which was identified as a strain of Delftia acidovorans, grew with N-acetyltaurine as carbon source and excreted stoichiometric amounts of sulfate and ammonium. Inducible enzyme activities were measured in crude extracts of this organism to elucidate the degradative pathway. Cleavage of N-acetyltaurine by a highly active amidase yielded acetate and taurine. The latter was oxidatively deaminated by taurine dehydrogenase to ammonium and sulfoacetaldehyde. This key intermediate of sulfonate catabolism was desulfonated by the known reaction of sulfoacetaldehyde acetyltransferase to sulfite and acetyl phosphate, which was further degraded to enter central metabolism. A degradative pathway including transport functions is proposed.
天然存在的磺酸盐N - 乙酰牛磺酸通过化学方法合成并确认了其特性。以能够利用N - 乙酰牛磺酸作为唯一固定氮源或唯一碳源的细菌进行需氧富集培养获得成功。一种代表性菌株NAT,被鉴定为食酸代尔夫特菌,它以N - 乙酰牛磺酸作为碳源生长,并按化学计量比分泌硫酸盐和铵。在该生物体的粗提取物中测量诱导酶活性以阐明降解途径。一种高活性酰胺酶对N - 乙酰牛磺酸的裂解产生乙酸盐和牛磺酸。后者被牛磺酸脱氢酶氧化脱氨生成铵和磺基乙醛。磺酸盐分解代谢的这个关键中间体通过磺基乙醛乙酰转移酶的已知反应脱硫生成亚硫酸盐和乙酰磷酸,后者进一步降解进入中心代谢。提出了一个包括转运功能的降解途径。