کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1976706 | 1060701 | 2007 | 8 صفحه PDF | دانلود رایگان |
Peptidoglycan recognition protein (PGRP) was isolated from immunized hemolymph of the wild silkworm, Samia cynthia ricini, detecting the biding activity with 125I-labeled peptidoglycan (PGN). The binding specificity of PGRP was tested by competitive inhibition of the binding to 125I-labeled-PGN by a large excess amount of non-labeled-PGN or other glucans. The binding to labeled uncross-linked Lys-type PGN from Micrococcus luteus was strongly inhibited by non-labeled-PGN of the same structure and meso-diaminopimelic acid (DAP)-type cross-linked PGN from Bacillus cell wall, but only a little by cross-linked PGN from M. luteus cell wall. The PGRP cDNA encodes a 193 amino acid open reading frame. The deduced amino acid sequence had 62 to 91% identities to known lepidopteran PGRPs, but less than 40% to Drosophila PGRPs. The PGRP gene constitutively expressed at a low level in naive fat body, and strongly induced by an injection of DAP-type cross-linked and Lys-type uncross-linked PGNs, but only weakly by Lys-type cross-linked PGN from M. luteus. The silkworm possibly distinguish between PGNs based on the structure of cross-linking peptide, but has less if any preference for the diamino acid residue of the stem peptide.
Journal: Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology - Volume 147, Issue 3, July 2007, Pages 512–519