Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042961 (volvulus)
 4,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A novel S100 ca2+-binding protein, termed calgranulin-related protein (CGRP), was purified to homogeneity from extracts of adult Onchocerca volvulus, a human tissue-dwelling parasite. Its complete amino acid sequence was determined using microanalytical techniques. The primary structure of CGRP consists of 91 residues and displays identity with the recently reported partial sequence of an S100 protein present in human neutrophils. The human origin of CGRP is supported by the occurrence in O. volvulus extracts of additional human neutrophil proteins, including migration inhibitory factor-related protein 8 and defensins. The results suggest that these proteins interact with the worm surface following their release by activated neutrophils in the course of inflammatory reactions caused by O. volvulus infection.
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PMID:Host-parasite interaction in human onchocerciasis: identification and sequence analysis of a novel human calgranulin. 861 76

The structure of the Ascaris allergen, ABA-1 was characterized at several levels. Purified allergen monomers eluted from reducing PAGE were found to reassociate into dimers in phosphate buffered saline containing 0.9 mM Ca2+. This association may involve the formation of disulfide bonds between monomers. The primary amino acid sequence was used to predict secondary structure and compare the allergen to other known proteins sequences. ABA-1 appears to be highly helical protein of two domains. Sequence analysis reveals short regions (25 amino acids) of high homology (76%) between ABA-1 and the major body wall myosin of Onchocerca volvulus. In addition, ABA-1 has sequence similarity to a family of EF-hand containing calcium binding proteins called S100 proteins. The dimerization and two-domain structure of ABA-1 is consistent with the possibility that ABA-1 is a member of the S100 family of calcium binding proteins.
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PMID:Structural characteristics of the Ascaris allergen, ABA-1. 913 43

The functions of the members of the S100 family of EF-hand proteins are modulated by calcium and, in a number of cases, by zinc or copper. One such protein is S100A12, which is implicated in inflammation and host-parasite responses. Previously, we reported the structures of human S100A12 in both low (dimeric) and high (hexameric) calcium forms and, in addition, that of a complex with copper and calcium. Here we report the crystal structures of the metal-free apo form of human S100A12 at 1.77 A resolution and of the zinc complex in two crystal forms (P2(1)2(1)2(1) and F222) to 1.88 A and 1.73 A resolution, respectively. These are the first structures of a zinc-only complex of an S100 protein to be determined. The zinc complex structure shows significant differences from those of both calcium-loaded and apo-S100A12 structures, and comparisons suggest an explanation for the zinc-induced 1500-fold increase in calcium affinity. In addition, the new structures provide insight into the role of zinc-calcium interplay in the transition of S100A12 from a dimer through a tetramer to a hexamer. The role of both zinc and calcium in target binding by S100A12 during host-parasite responses is confirmed by experiments with paramyosin from the tropical parasites Onchocerca volvulus and Brugia malayi.
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PMID:The crystal structures of human S100A12 in apo form and in complex with zinc: new insights into S100A12 oligomerisation. 1950 94