Characterization of luminal paneth cell alpha-defensins in mouse small intestine. Attenuated antimicrobial activities of peptides with truncated amino termini.
Characterization of luminal paneth cell alpha-defensins in mouse small intestine. Attenuated antimicrobial activities of peptides with truncated amino termini.
复制标题
DOI：
10.1074/jbc.m004062200
复制
发表时间：
2000-10
期刊：
影响因子：
--
通讯作者：
A. J. Ouellette;Donald P. Satchell;Matthew M. Hsieh;Susan J. Hagen;M. Selsted
中科院分区：
文献类型：
--
作者：
A. J. Ouellette;Donald P. Satchell;Matthew M. Hsieh;Susan J. Hagen;M. Selsted
位于小肠隐窝底部的潘氏细胞分泌含有抗微生物肽的顶端颗粒，所述抗微生物肽包括称为隐窝素的α-防御素。使用小鼠cryptdin-1、-2、-3和-6的特异性抗体，免疫金定位研究表明cryptdin是小鼠潘氏细胞分泌颗粒的成分。用凝胶过滤和反相高效液相色谱法从成年小鼠小肠冲洗液中分离纯化了几种Cryptdin多肽。通过肽序列测定确定了它们的一级结构，并将它们的抗菌活性与相应组织形式的抗菌活性进行了比较。分离的腔穴蛋白包括与组织形式的穴蛋白-2、-4和-6相同的肽，以及N末端截短一个或两个残基的穴蛋白-1、-4和-6的变体。在对金黄色葡萄球菌、大肠杆菌和对防御素敏感的鼠伤寒沙门氏菌phoP（-）突变体的抗微生物活性的测定中，全长cryptdins无论是从组织还是从管腔中分离都具有相同的体外抗微生物活性。相比之下，N-末端截短的（des-Leu），（des-Leu-Arg）-cryptdin-6和（des-Gly）-cryptdin-4肽的活性明显较低。研究了重组cryptdin-4和（des-Gly）-cryptdin-4多肽对大肠杆菌的抑菌活性。coli和S.鼠伤寒沙门氏菌的研究表明，N-末端Gly残基或cryptdin-4 N末端的长度是杀微生物活性的决定因素。先天免疫的隐窝腔可以调制的氨基肽酶修饰后，肽分泌的α-防御素。
Paneth cells at the base of small intestinal crypts secrete apical granules that contain antimicrobial peptides including alpha-defensins, termed cryptdins. Using an antibody specific for mouse cryptdin-1, -2, -3, and -6, immunogold-localization studies demonstrated that cryptdins are constituents of mouse Paneth cell secretory granules. Several cryptdin peptides have been purified from rinses of adult mouse small intestine by gel filtration and reverse-phase high performance liquid chromatography. Their primary structures were determined by peptide sequencing, and their antimicrobial activities were compared with those of the corresponding tissue forms. The isolated luminal cryptdins included peptides identical to the tissue forms of cryptdin-2, -4, and -6 as well as variants of cryptdin-1, -4, and -6 that have N termini truncated by one or two residues. In assays of antimicrobial activity against Staphylococcus aureus, Escherichia coli, and the defensin-sensitive Salmonella typhimurium phoP(-) mutant, full-length cryptdins had the same in vitro antibacterial activities whether isolated from tissue or from the lumen. In contrast, the N-terminal-truncated (des-Leu), (des-Leu-Arg)-cryptdin-6, and (des-Gly)-cryptdin-4 peptides were markedly less active. The microbicidal activities of recombinant cryptdin-4 and (des-Gly)-cryptdin-4 peptides against E. coli, and S. typhimurium showed that the N-terminal Gly residue or the length of the cryptdin-4 N terminus are determinants of microbicidal activity. Innate immunity in the crypt lumen may be modulated by aminopeptidase modification of alpha-defensins after peptide secretion.