NUCLEOTIDE-SEQUENCE OF THE STREPTOCOCCUS-GORDONII PK488 COAGGREGATION ADHESIN GENE, SCAA, AND ATP-BINDING CASSETTE
NUCLEOTIDE-SEQUENCE OF THE STREPTOCOCCUS-GORDONII PK488 COAGGREGATION ADHESIN GENE, SCAA, AND ATP-BINDING CASSETTE
复制标题
DOI：
10.1128/iai.62.10.4469-4480.1994
复制
发表时间：
1994-10-01
影响因子：
3.1
通讯作者：
GANESHKUMAR, N
中科院分区：
文献类型：
--
作者：
KOLENBRANDER, PE;ANDERSEN, RN;GANESHKUMAR, N
与内氏放线菌PK 606共聚集的人口腔草绿色组链球菌表达与ScaA相关的表面蛋白，ScaA是戈登链球菌PK 488（R. N，Andersen，N，Ganeshkumar，and P. E，Kolenbrander，Infect. Immun. 61：981-987，1993）。确定了pRA 1的6，125-bp EcoRI插入片段的核苷酸序列，该插入片段包含编码ScaA的基因scaA。鉴定了6个开放阅读框（ORF）。4个ORF的方向，两个上游（ORF 1和ORF 2）和一个下游（ORF 4）的scaA（ORF 3），表明转录在一个方向，而ORF 5和ORF 6转录发散。对推导的氨基酸序列的计算机分析鉴定了由ORF 1编码的推定的28，054-Da蛋白中的ATP（GxxGxGKS）的共有结合位点。ORF 2编码的疏水蛋白分子量为29，705 Da，具有6个跨膜区。ScaA是310个氨基酸，34，787 Da，并且含有脂蛋白共有序列LxxC，也报道了分别来自血链球菌12、副血链球菌FW 213和肺炎链球菌R36 A的ScaA相关蛋白SsaB、FimA和PsaA。ORF 4可能编码163个氨基酸的蛋白质，分子量为17，912 Da，与ssaB、fim-A和psaA的下游相邻基因产物几乎相同。ORF 5基因产物与其他蛋白质没有明显的同源性，ORF 6是不完整的，编码一个大于564个氨基酸的蛋白质，ORF 5基因产物由229个氨基酸组成，分子量为25，107 Da。这种推定的蛋白质有一个共识的锌+结合基序，HExxH，细菌嗜热菌蛋白酶和哺乳动物中性内肽酶之间发现，是40%相同的同源210个氨基酸的区域的人脑啡肽酶。ORF 1、2和3的遗传组织与革兰氏阴性菌的细菌周质结合蛋白依赖性转运系统和革兰氏阳性菌的结合脂蛋白依赖性转运系统的遗传组织相似，并且这些基因似乎编码ABC（ATP结合盒）蛋白。本报告描述了与ATP结合盒相关的细胞间粘附功能。
Human oral viridans group streptococci that coaggregate with Actinomyces naeslundii PK606 express surface proteins related to ScaA, the coaggregation-mediating adhesin of Streptococcus gordonii PK488 (R. N, Andersen, N, Ganeshkumar, and P. E, Kolenbrander, Infect. Immun. 61:981-987, 1993). The nucleotide sequence of the 6,125-bp EcoRI insert of pRA1, containing scaA, the gene encoding ScaA, was determined. Six open reading frames (ORFs) were identified. The orientation of four ORFs, two upstream (ORF 1 and ORF 2) and one downstream (ORF 4) of scaA (ORF 3), indicated transcription in one direction, whereas ORF 5 and ORF 6 were transcribed divergently. Computer analysis of the deduced amino acid sequences identified a consensus binding site for ATP (GxxGxGKS) in the putative 28,054-Da protein encoded by ORF 1. ORF 2 potentially encoded a hydrophobic protein of 29,705 Da with six potential membrane-spanning regions. ScaA was 310 amino acids, 34,787 Da, and contained the lipoprotein consensus sequence LxxC, also reported for the ScaA-related proteins SsaB, FimA, and PsaA from Streptococcus sanguis 12, Streptococcus parasanguis FW213, and Streptococcus pneumoniae R36A, respectively. ORF 4 potentially encoded a 163-amino-acid protein of 17,912 Da, which was nearly identical to the downstream adjacent gene products of ssaB, fim-A, and psaA. No significant homology with other proteins was found with the putative ORF 5 gene product, a 229-amino-acid protein of 25,107 Da. ORF 6 was incomplete and encoded a protein larger than 564 amino acids. This putative protein had a consensus Zn2+ binding motif, HExxH, found among bacterial thermolysins and mammalian neutral endopeptidases and was 40% identical to a homologous 210-amino-acid region of human enkephalinase. The genetic organization of ORFs 1, 2, and 3 was similar to those of the bacterial periplasmic-binding protein-dependent transport systems of gram-negative bacteria and binding-lipoprotein-dependent transport systems of gram-positive bacteria, and these genes appeared to encode ABC (ATP-binding cassette) proteins. This report describes a cell-to-cell adherence function associated with an ATP-binding cassette.