Release of the cell-envelope protease PrtS in the growth medium of Streptococcus thermophilus 4F44
Release of the cell-envelope protease PrtS in the growth medium of Streptococcus thermophilus 4F44
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DOI：
10.1016/j.idairyj.2011.10.014
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发表时间：
2012-04-01
影响因子：
3.1
通讯作者：
Dary, Annie
中科院分区：
文献类型：
--
作者：
Chang, Oun Ki;Perrin, Clarisse;Dary, Annie
PRTS是嗜热链球菌唯一的细胞包膜蛋白(CEP)。据认为，它是通过存在于其C-末端的LPXTG基序由Sortase A((SrtA)锚定在细胞壁上的。在嗜热链霉菌4F44的上清液中检测到两种对应于PRTS的可溶酶：酶原和成熟蛋白。在该菌株中，60%的PRTS分子固定在细胞壁上，40%释放在培养基中。这种释放可能是由于SrtA菌株4F44的部分缺失造成的，即使它的序列与锚定PRTS的嗜热链球菌LMD-9略有不同。事实上，在所释放的酶的C-末端存在完整的LPXTG基序，这表明没有发生由SrtA驱动的连接过程，并且这些酶在锚定后不会通过蛋白分解释放。(C)爱思唯尔有限公司出版的2012年。
PrtS is the sole cell envelope protease ((CEP) characterized in Streptococcus thermophilus. It is believed that it is anchored to the cell wall by sortase A ((SrtA) through the LPXTG motif present at its C-terminus. Two soluble proteases corresponding to PrtS in its proenzyme and mature form were detected in the supernatant of S. thermophilus strain 4F44. In this strain, 60% of the PrtS molecules are anchored to the cell wall and 40% released in the medium. Such a release might result from a partial deficiency in the strain 4F44 of SrtA, even if its sequence slightly differs from that of S. thermophilus strain LMD-9, in which PrtS is anchored. Indeed, the presence of an intact LPXTG motif at the C-terminus of the released proteases showed that the linking process driven by SrtA did not occur and these proteases were not released by proteolysis after their anchoring. (C) 2012 Published by Elsevier Ltd.