Candido E P, Dixon G H
Proc Natl Acad Sci U S A. 1972 Aug;69(8):2015-9. doi: 10.1073/pnas.69.8.2015.
The sequences of the first 25 residues of histone III, and the first 22 residues of histone IIb(2), from trout testis have been determined on an automatic protein sequencer. The amino-terminal sequence of trout-testis histone III is identical to the corresponding region of calfthymus histone III, whereas the trout-testis histone IIb(2) sequence differs from that of calf-thymus histone IIb(2) at several positions in the amino-terminal region. Several in vivo sites of acetylation of these trout-testis histones have also been determined, by the same automated procedure. In addition to the two main sites at lysyl residues 14 and 23 acetylated in calf-thymus histone III, a lower degree of acetylation at two other sites, lysyl residues 9 and 18, has been detected. Four sites of acetylation have also been detected in trout-testis histone IIb(2), at lysyl residues 5, 10, 13, and 18. When the amino-acid sequences around the acetylated lysyl residues of different histones are compared, striking similarities are seen. The methods used in these studies should prove useful in elucidation of the locations of chemically stable modifications in other proteins.
已使用自动蛋白质测序仪测定了来自鲑鱼睾丸的组蛋白III前25个残基的序列以及组蛋白IIb(2)前22个残基的序列。鲑鱼睾丸组蛋白III的氨基末端序列与小牛胸腺组蛋白III的相应区域相同，而鲑鱼睾丸组蛋白IIb(2)序列在氨基末端区域的几个位置与小牛胸腺组蛋白IIb(2)的序列不同。这些鲑鱼睾丸组蛋白体内的几个乙酰化位点也已通过相同的自动化程序确定。除了小牛胸腺组蛋白III中赖氨酸残基14和23处的两个主要乙酰化位点外，还检测到另外两个位点（赖氨酸残基9和18）的较低程度的乙酰化。在鲑鱼睾丸组蛋白IIb(2)中也检测到四个乙酰化位点，分别在赖氨酸残基5、10、13和18处。当比较不同组蛋白的乙酰化赖氨酸残基周围的氨基酸序列时，可以看到明显的相似性。这些研究中使用的方法在阐明其他蛋白质中化学稳定修饰的位置方面应该会被证明是有用的。
