Suzuki Y, Murachi T
J Biochem. 1978 Oct;84(4):977-84. doi: 10.1093/oxfordjournals.jbchem.a132212.
Rat peritoneal macrophages are known to contain a chymotrypsin-like neutral protease associated with a specific inhibitor. By homogenizing the cells in 0.25 M sucrose (pH 8.0) containing 0.5% Triton X-100, both the protease and the inhibitor were found to be localized in the nuclei, particularly in chromatin. The inhibitory factor in chromatin was then separated from the protease by hydroxylapatite gel chromatography in the presence of 2 M NaCl and 5 M urea. The inhibitor fraction obtained was deproteinized by digestion with Pronase and subsequent extraction with phenol; these treatments did not alter the inhibitory potency. The deproteinized inhibitor fraction had a UV absorption ratio, A280/A260, of 0.61, but it was resistant to digestion with various nucleases, including DNase 1, nuclease P1, and snake venom phosphodiesterase. However, when it was incubated with poly(ADP-ribose) glycohydrolase from calf thymus, the inhibitory potency was markedly decreased. An authentic poly(ADP-ribose), with a mean chain length of approximately 30 ADP-ribose units, produced significant inhibition of the neutral protease isolated from macrophage chromatin. No such inhibition was produced by DNA, single-stranded DNA, RNA, polyadenylate, polyuridylate, polycytidylate, or monomeric ADP-ribose.
已知大鼠腹膜巨噬细胞含有一种与特定抑制剂相关的类胰凝乳蛋白酶中性蛋白酶。通过在含有0.5% Triton X - 100的0.25 M蔗糖（pH 8.0）中匀浆细胞，发现蛋白酶和抑制剂都定位于细胞核中，特别是在染色质中。然后在2 M NaCl和5 M尿素存在下，通过羟基磷灰石凝胶色谱法将染色质中的抑制因子与蛋白酶分离。得到的抑制剂组分用链霉蛋白酶消化并随后用苯酚提取进行脱蛋白处理；这些处理并未改变抑制效力。脱蛋白的抑制剂组分的紫外吸收比A280/A260为0.61，但它对包括DNase 1、核酸酶P1和蛇毒磷酸二酯酶在内的各种核酸酶的消化具有抗性。然而，当它与来自小牛胸腺的聚（ADP - 核糖）糖苷水解酶一起孵育时，抑制效力显著降低。平均链长约为30个ADP - 核糖单位的 authentic 聚（ADP - 核糖）对从巨噬细胞染色质中分离出的中性蛋白酶产生了显著抑制作用。DNA、单链DNA、RNA、聚腺苷酸、聚尿苷酸、聚胞苷酸或单体ADP - 核糖均未产生这种抑制作用。 （注：这里“authentic”不太明确准确意思，可能是“真实的、正宗的”等，暂按原样翻译）
