Malchy B L
Biochemistry. 1977 Aug 23;16(17):3922-7. doi: 10.1021/bi00636a031.
The reactivity of the amino groups of the five histones towards acetic anhydride has been measured and with the exception of histone IIb2 the reactivities are very similar to those of exposed lysines with an average pK of 9.5. In addition the reactivities of these groups from 0.20 to 1.0 M NaCl and the reactivity of a peptide containing lysines 5, 8, 12 and 16 of histone IV have been measured in chromatin. It is concluded that at the lower ionic strengths the large proportion of the amino groups are buried for both the histones and the region of histone IV studied. Data obtained from the measurement of the reactivity of standard proline compounds and from a pH and ionic strength study indicate that the N-terminal proline of histone IIb2 is exposed.
已对五种组蛋白的氨基与乙酸酐的反应活性进行了测定，除组蛋白IIb2外，其他组蛋白的反应活性与平均pK为9.5的暴露赖氨酸的反应活性非常相似。此外，还测定了这些基团在0.20至1.0 M氯化钠中的反应活性以及染色质中含有组蛋白IV的赖氨酸5、8、12和16的肽的反应活性。得出的结论是，在较低离子强度下，所研究的组蛋白和组蛋白IV区域中的大部分氨基都被掩埋。从标准脯氨酸化合物反应活性的测量以及pH和离子强度研究获得的数据表明，组蛋白IIb2的N端脯氨酸是暴露的。
