The gene encoding a Prevotella loescheii lectin-like adhesin contains an interrupted sequence which causes a frameshift.
The gene encoding a Prevotella loescheii lectin-like adhesin contains an interrupted sequence which causes a frameshift.
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编码普氏菌凝集素样粘附素的基因包含导致移码的中断序列。
DOI：
10.1128/jb.174.22.7328-7336.1992
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发表时间：
1992
影响因子：
3.2
通讯作者：
London,J
中科院分区：
文献类型：
--
作者：
Manch-Citron,JN;Allen,J;MoosJr,M;London,J
我们克隆并测序了洛氏普雷沃菌基因plaA，该基因编码一种凝集素样粘附素，介导洛氏普雷沃菌1295与口腔链球菌34的共聚集。使用衍生自纯化的粘附素的N-末端氨基酸序列的探针来鉴定来自在λ GEM-11中构建的洛氏毕赤酵母基因组文库的plaA基因。plaA的序列分析表明，最初的翻译产物含有一个22个氨基酸的前导序列。plaA基因的阅读框在成熟蛋白的氨基酸28之后被TAA终止密码子中断。通过聚合酶链反应扩增该密码子周围区域中的洛氏毕赤酵母基因组DNA，然后对克隆的DNA片段进行DNA测序，确定该终止密码子不是实验人工产物。需要从赭石终止子下游29 bp处开始移码，以进入基因中唯一的大开放阅读框。通过用内切蛋白酶Lys-C对粘附素进行有限蛋白水解得到的6个纯化肽的氨基酸序列与通过大开放阅读框翻译得到的下游氨基酸序列相匹配。2.4kb的基因编码序列包含用于合成89-kDa蛋白质的足够信息。一个假定的rho-非依赖性终止子（Δ G = -25.5 kcal/mol [ca. -107 kJ/mol]）。
We cloned and sequenced the Prevotella loescheii gene plaA, which encodes a lectin-like adhesin that mediates the coaggregation of P. loescheii 1295 with Streptococcus oralis 34. A probe derived from the N-terminal amino acid sequence of the purified adhesin was used to identify the plaA gene from a P. loescheii genomic library constructed in lambda GEM-11. Sequence analysis of plaA indicates that the initial translation product contains a 22-amino-acid leader. The reading frame of the plaA gene is interrupted after amino acid 28 of the mature protein by a TAA termination codon. Amplification of the P. loescheii genomic DNA in the region surrounding this codon by the polymerase chain reaction followed by DNA sequencing of the cloned DNA fragment established that this stop codon was not an experimental artifact. A frameshift beginning 29 bp downstream of the ochre terminator was required to access the only large open reading frame in the gene. Amino acid sequences of six purified peptides derived by limited proteolysis of adhesin with endoproteinase Lys-C matched the downstream amino acid sequence derived by translation of the large open reading frame. The gene coding sequence of 2.4 kb contains sufficient information for the synthesis of an 89-kDa protein. A putative rho-independent terminator (delta G = -25.5 kcal/mol [ca. -107 kJ/mol]) was detected 38 bp downstream from the plaA stop codon.