Bonnarme P, Arfi K, Dury C, Helinck S, Yvon M, Spinnler H E
Institut National de la Recherche Agronomique, Laboratoire de Génie et Microbiologie de Procédés Alimentaires, Thiverval-Grignon, France.
FEMS Microbiol Lett. 2001 Dec 18;205(2):247-52. doi: 10.1111/j.1574-6968.2001.tb10956.x.
L-methionine degradation products and catabolic enzymatic activities involved in methanethiol generation were investigated in Geotrichum candidum GcG. L-methionine was easily degraded by G. candidum and the transamination product, 4-methylthio-2-oxobutyric acid (KMBA), was found to transiently accumulate. In parallel, considerable L-methionine aminotransferase activity was found in this microorganism. L-methionine and KMBA demethiolating activities were also detected. The degradation of KMBA corresponded to an overall increase in the production of volatile sulfur compounds. These results show that the transamination pathway is of major importance in the initial breakdown of L-methionine by this cheese-ripening microorganism.
研究了白地霉GcG中参与甲硫醇生成的L-甲硫氨酸降解产物和分解代谢酶活性。白地霉能轻易降解L-甲硫氨酸,且发现其转氨产物4-甲硫基-2-氧代丁酸(KMBA)会短暂积累。同时,在这种微生物中发现了相当高的L-甲硫氨酸转氨酶活性。还检测到了L-甲硫氨酸和KMBA的脱甲硫醇活性。KMBA的降解对应于挥发性硫化合物产量的总体增加。这些结果表明,转氨途径在这种奶酪成熟微生物对L-甲硫氨酸的初始分解中起主要作用。