Staphylococcus caprae strains carry determinants known to be involved in pathogenicity:: a gene encoding an autolysin-binding fibronectin and the ica operon involved in biofilm formation
Staphylococcus caprae strains carry determinants known to be involved in pathogenicity:: a gene encoding an autolysin-binding fibronectin and the ica operon involved in biofilm formation
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DOI：
10.1128/iai.69.2.712-718.2001
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发表时间：
2001-02-01
影响因子：
3.1
通讯作者：
El Solh, N
中科院分区：
文献类型：
--
作者：
Allignet, J;Aubert, S;El Solh, N
从一株葡萄球菌感染分离株的染色体中分离出编码与纤维连接蛋白结合的自溶素的atlC基因（1485 bp）和参与生物膜形成的ica操纵子，并对其进行了测序。AtlC （155 kDa）类似于葡萄球菌的自溶酶Atl、AtlE、Aas（48 - 72%的氨基酸同源性），含有一个假定的由29个氨基酸组成的信号肽和两个酶中心（n-乙酰muramyl - l-丙氨酸氨基酶和内- β - n-乙酰氨基葡萄糖苷酶），由三个不完全的纤维连接蛋白结合重复序列相互连接。在每个重复序列的中心和末端发现的甘氨酸-色氨酸（GW）基序可能像在单核增生李斯特菌中一样，用于atc的细胞表面锚定。S， caprae ica操纵子包含4个与S，表皮和S， aureus icaA、icaB、icaC和icaD基因密切相关的基因（相似度大于或等于68%），前面有一个与icaR相似的基因（相似度大于或等于70%）。从S， caprae ica基因推断出的多肽与S，表皮和S， aureus ica基因的氨基酸同源性为67 ~ 88%。对14株S、caprae菌株的icaR操纵子和icaR基因进行了分析，其中一些菌株产生生物膜，另一些没有。所有菌株携带的ica操纵子和icaR的大小和相对位置相同，这表明没有形成生物膜与插入可移动元件（如插入序列或转座子）无关。
The atlC gene (1,485 bp), encoding an autolysin which binds fibronectin, and the ica operon, involved in biofilm formation, were isolated from the chromosome of an infectious isolate of Staphylococcus caprae and sequenced. AtlC (155 kDa) is similar to the staphylococcal autolysins Atl, AtlE, Aas (48 to 72% amino acid identity) and contains a putative signal peptide of 29 amino acids and two enzymatic centers (N-acetylmuramoyl-L-alanine amidase and endo-beta -N-acetylglucosaminidase) interconnected by three imperfect fibronectin-binding repeats. The glycine-tryptophan (GW) motif found in the central and end part of each repeat may serve for cell surface anchoring of AtlC as they do in Listeria monocytogenes. The S, caprae ica operon contains four genes closely related to S, epidermidis and S, aureus icaA, icaB, icaC, and icaD genes (greater than or equal to 68% similarity) and is preceded by a gene similar to icaR (greater than or equal to 70% similarity). The polypeptides deduced from the S, caprae ica genes exhibit 67 to 88% amino acid identity to those of S, epidermidis and S, aureus ica genes. The ica operon and icaR gene were analyzed in 14 S, caprae strains from human specimens or goats' milk Some of the strains produced biofilm, and others did not. All strains carry the ica operon and icaR of the same sizes and in the same relative positions, suggesting that the absence of biofilm formation is not related to the insertion of a mobile element such as an insertion sequence or a transposon.