IDENTIFICATION AND CHARACTERIZATION OF THE GENES ENCODING 3-STRUCTURAL PROTEINS OF THE SULFOLOBUS VIRUS-LIKE PARTICLE SSV1
IDENTIFICATION AND CHARACTERIZATION OF THE GENES ENCODING 3-STRUCTURAL PROTEINS OF THE SULFOLOBUS VIRUS-LIKE PARTICLE SSV1
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DOI：
10.1007/bf00326550
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发表时间：
1987-01-01
期刊：
影响因子：
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通讯作者：
GRAMPP, B
中科院分区：
文献类型：
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作者：
REITER, WD;PALM, P;GRAMPP, B
对嗜热嗜酸古细菌硫化叶菌B12株的病毒样颗粒SSV 1的结构蛋白VP 1、VP 2和VP 3进行了纯化。VP 1和VP 3是非常疏水的，并且显示出高度的同源性。它们分别由73和92个氨基酸残基组成。第三种蛋白质VP 2是非常碱性的，含有29个碱性氨基酸，但在总共74个氨基酸残基中只有4个酸性氨基酸。通过比较N-末端氨基酸序列与SSV 1 DNA序列，将编码这三种蛋白质的基因定位在基因组内。这三个基因以VP 1-VP 3-VP 2的顺序紧密连锁，并且所有三个基因的编码链是相同的。十个核苷酸将VP 1的终止密码子与VP 3的起始密码子分开，一个核苷酸将编码VP 3和VP 2的基因分开。在VP 2和VP 3的起始密码子上游发现了重复的推定核糖体结合位点。主要外壳蛋白VP 1不以甲硫氨酸残基开始，并且似乎是前体分子的蛋白水解裂解的结果。编码VP 1、VP 2和VP 3的区域的转录导致形成0.5kb和1.0kb的两个mRNA，较短的一个仅编码VP 1，较长的一个跨越所有三个基因。编码VP 1部分的61 bp序列在VP 3基因内完全重复，这些相同的序列在两种蛋白质中翻译成相同的氨基酸片段。这种重复的DNA序列的功能很可能超出其编码特性。
Three structural proteins, VP1, VP2 and VP3, of the virus-like particle SSV1 of the thermoacidophilic archaebacterium Sulfolobus sp. strain B12 were purified. VP1 and VP3 are very hydrophobic and show a high degree of homology. They consist of 73 and 92 amino acid residues, respectively. The third protein VP2, is extremely basic containing 29 basic amino acids but only 4 acidic ones in a total of 74 amino acids residues. The genes encoding these three proteins were mapped within the genome by comparison of N-terminal amino acid sequences with the SSV1 DNA sequence. The three genes are closely linked in the order VP1-VP3-VP2 and the coding strand is the same in all three genes. Ten nucleotides separate the stop codon for VP1 from the initiation codon for VP3 and one nucleotide separates the genes encoding VP3 and VP2. Duplicate putative ribosome binding sites are found upstream of the initiation codons for VP2 and VP3. The major coat protein VP1 does not start with a methionine residue and appears to be the result of proteolytic cleavage of a precursor molecule. Transcription of the region encoding VP1, VP2 and VP3 results in the formation of two mRNAs of 0.5 kb and 1.0 kb, the shorter one only encoding VP1, the longer one spanning all three genes. A 61 bp sequence encoding part of VP1 is exactly repeated within the gene for VP3 and these identical sequences are translated into stretches of identical amino acids in the two proteins. A function of this repeated DNA sequence beyond its coding properties is very likely.