GLMS OF THERMUS-THERMOPHILUS HB8 - AN ESSENTIAL GENE FOR CELL-WALL SYNTHESIS IDENTIFIED IMMEDIATELY UPSTREAM OF THE S-LAYER GENE
GLMS OF THERMUS-THERMOPHILUS HB8 - AN ESSENTIAL GENE FOR CELL-WALL SYNTHESIS IDENTIFIED IMMEDIATELY UPSTREAM OF THE S-LAYER GENE
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DOI：
10.1111/j.1365-2958.1995.mmi_17010001.x
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发表时间：
1995-07-01
影响因子：
3.6
通讯作者：
BERENGUER, J
中科院分区：
文献类型：
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作者：
FERNANDEZHERRERO, LA;BADETDENISOT, MA;BERENGUER, J
从 lambda 噬菌体基因库中克隆了含有来自嗜热栖热菌 HB8 的 S 层基因 (slpA) 的 30 kbp 染色体区域。对 slpA 基因上游区域的 DNA 序列分析揭示了开放阅读框 (ORF) 的存在，该开放阅读框编码与原核和真核起源的葡萄糖胺-6-P 合酶 (EC 2.6.1.16) 高度同源的 604 个氨基酸蛋白质。已使用三种不同的策略将该 ORF 鉴定为来自嗜热菌 (glmS(th)) 的葡萄糖胺-6-P 合酶基因：(i) 大肠杆菌 glmS 突变体的互补； (ii) 基因的体内插入失活； (iii) 通过过量生产的大肠杆菌菌株的细胞质提取物在 60 摄氏度下体外合成葡萄糖胺-6-P。 glmS(th) 基因与 slpA 不同地转录为 2.0 kb mRNA，该 mRNA 可能还包括在其 3' 末端鉴定的色氨酸 tRNA 基因 (trpT(th))。由于 glmS(th) 和 slpA 基因的产物都是嗜热链球菌细胞被膜的主要成分，它们在染色体中的异常聚集可能与其协调表达的特定机制的存在有关。
A 30 kbp chromosomal region containing the S-layer gene (slpA) from Thermus thermophilus HB8 was cloned from a lambda phage gene library. DNA sequence analysis of the region upstream to the slpA gene revealed the presence of an open reading frame (ORF) which coded for a 604-amino-acid protein highly homologous to the glucosamine-6-P synthases (EC 2.6.1.16) of both prokaryotic and eukaryotic origin. The identification of this ORF as the glucosamine-6-P synthase gene from T. thermophilus (glmS(th)) has been carried out using three different strategies: (i) complementation of an Escherichia coli glmS mutant; (ii) in vivo insertional inactivation of the gene; and (iii) in vitro synthesis of glucosamine-6-P at 60 degrees C by a cytoplasmic extract of an overproducing E. coli strain. The glmS(th) gene is transcribed divergently from slpA in a 2.0 kb mRNA which probably also includes a tryptophan tRNA gene (trpT(th)) identified at its 3' extreme. As the products of both the glmS(th) and the slpA genes are main components of the cell envelope of T. thermophilus, their unusual clustering in the chromosome could be related to the existence of specific mechanisms for their coordinate expression.