MOLECULAR EVOLUTION OF LYTIC ENZYMES OF STREPTOCOCCUS-PNEUMONIAE AND ITS BACTERIOPHAGES
MOLECULAR EVOLUTION OF LYTIC ENZYMES OF STREPTOCOCCUS-PNEUMONIAE AND ITS BACTERIOPHAGES
复制标题
DOI：
10.1073/pnas.85.3.914
复制
发表时间：
1988-02-01
影响因子：
11.1
通讯作者：
LOPEZ, R
中科院分区：
文献类型：
--
作者：
GARCIA, E;GARCIA, JL;LOPEZ, R
肺炎球菌噬菌体CP-1 DNA的2.9kb的Acc I片段包含Cp1基因，与编码肺炎球菌酰胺酶的lytA基因杂交。CP-1的Cp1基因编码溶菌胺酶(CPL)，其核苷酸序列已确定。Cp1和lytA编码序列的3‘’区具有相当大的核苷酸序列同源性，推导的氨基酸序列的羧基末端结构域非常相似：在Cp1和lytA编码的142个氨基酸残基中，有73个是相同的，在69个替换中，55个是保守的。沙棘真菌CPL、肺炎链球菌酰胺酶和胞壁酰胺酶的比较。(一种也能降解肺炎球菌细胞壁的酶)强烈地表明，CPL和酰胺酶的羧基末端结构域可能负责含有胆碱的细胞壁的特异性识别，以及肺炎球菌脂磷壁酸或高浓度胆碱对这些酶的催化活性的非竞争性抑制。此外，这些酶的活性中心应该位于它们的氨基末端结构域。我们的结果表明噬菌体和宿主赖氨酸之间存在进化关系。
A 2.9-kilobase Acc I fragment of the DNA of the pneumococcal bacteriophage Cp-1, containing the cpl gene, hybridizes with the lytA gene encoding the pneumococcal amidase. The nucleotide sequence of the cpl gene of Cp-1, encoding a muramidase (CPL), has been determined. The 3'' regions of the cpl and lytA coding sequences show considerable nucleotide sequence homology and the carboxyl-terminal domains of the deduced amino acid sequences of these lysins are quite similar: 73 of the carboxyl-terminal 142 amino acid residues are identical, and of the 69 substitutions, 55 are conservative. Comparisons between CPL, the pneumococcal amidase, and the muramidase of the fungus Chalaropsis sp. (an enzyme that also degrades the pneumococcal cell wall) strongly suggest that the carboxyl-trerminal domains of CPl and of the amidase might be responsible for the specific recognition of choline-containing cell walls, as well as for the noncompetitive inhibition of the catalytic activity of these enzymes by the pneumococcal lipoteichoic acid or by high concentrations of choline. In addition, the active center of these enzymes should be located in their amino-terminal domains. Our results suggest an evolutionary relationship between phage and host lysins.