肺炎克雷伯菌glnB基因的鉴定：野生型和突变等位基因的核苷酸序列

Identification of the Klebsiella pneumoniae glnB gene: nucleotide sequence of wild-type and mutant alleles.

作者信息

Holtel A, Merrick M

机构信息

AFRC Institute of Plant Science Research, University of Sussex, Brighton, UK.

出版信息

Mol Gen Genet. 1988 Dec;215(1):134-8. doi: 10.1007/BF00331314.

DOI:10.1007/BF00331314

Abstract

The glnB gene of Klebsiella pneumoniae, which encodes the nitrogen regulation protein PII, has been cloned and sequenced. The gene encodes a 12429 dalton polypeptide and is highly homologous to the Escherichia coli glnB gene. The sequences of a glnB mutation which causes glutamine auxotrophy and of a Tn5 induced Gln+ suppressor of this mutation were also determined. The glutamine auxotrophy was deduced to be the result of a modification of the uridylylation site of PII, and the suppression was shown to be caused by Tn5 insertion in glnB. The 3' end of an open reading frame of unknown function was identified upstream of glnB and may be part of an operon containing glnB. Potential homologues of glnB encoding polypeptides extremely similar in sequence to PII were identified upstream of published sequences of the glutamine synthetase structural gene (glnA) in Rhizobium leguminosarum, Bradyrhizobium japonicum and Azospirillum brasilense.

摘要

肺炎克雷伯菌的glnB基因已被克隆和测序，该基因编码氮调节蛋白PII。该基因编码一个12429道尔顿的多肽，与大肠杆菌的glnB基因高度同源。还确定了导致谷氨酰胺营养缺陷型的glnB突变序列以及该突变的Tn5诱导的Gln + 抑制子序列。谷氨酰胺营养缺陷型被推断是PII尿苷酸化位点修饰的结果，并且抑制作用被证明是由Tn5插入glnB引起的。在glnB上游鉴定出一个功能未知的开放阅读框的3'末端，它可能是包含glnB的操纵子的一部分。在豆科根瘤菌、日本慢生根瘤菌和巴西固氮螺菌的谷氨酰胺合成酶结构基因（glnA）的已发表序列上游，鉴定出了编码与PII序列极其相似的多肽的glnB潜在同源物。