Partial characterization and purification of a rabbit granulocyte factor that increases permeability of Escherichia coli.
AUTOR(ES)
Weiss, J
RESUMO
Recently we reported that rapid killing of Escherichia coli by granulocytes or granulocyte fractions is accompanied by an equally rapid and discrete increase in permeability of the microbial envelope (Beckerdite, Mooney, Weiss, Franson, and Elsbach. 1974. J. Exp. Med. 140: 396-409). Most of this permeability-increasing activity (PI) is found in a crude granule preparation. PI is quantitatively recovered in a 23,000-g supernatant fraction (Sup II) after sulfuric acid extraction of granulocyte homogenates prepared in water. PI is nondialyzable, destroyed by pronase and trypsin, stable at 4degreesC for at least 2 mo, and destroyed by heating at 94degreesC. Anionic substances, such as heparin sulfate and isolated E. coli lipopolysaccharide, bind to and inhibit PI. PI has been purified up to 1,000-fold from homogenate in a yield of 50percent by acid extraction and carboxymethyl-Sephadex chromatography. Such purified fractions have bactericidal activity that equals that of disrupted granulocytes and Sup II, are similarly enriched with respect to granule-associated phospholipase, and protease activities. Whereas E. coli, sensitive to PI, binds or inactivates solubilized PI, a resistant strain of Serratia marcescens does not. Binding of PI to sensitive microorganisms seems to be necessary for expression of its biological activity since both the apparent binding to and the biological effect of PI on E. coli are completely blocked by 10-20 mM Mg2+ or Ca2+. Mg2+ or Ca2+ can reverse the effect on E. coli permeability produced by Sup II or the carboxymethyl-Sephadex fraction but not that produced by granulocyte homogenate. The close association of bactericidal, phospholipase A2, and permeability-increasing activities towards several gram-negative bacterial species suggests that they may be related.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=301714Documentos Relacionados
- Partial purification and characterization of a heat-labile enterotoxin of Escherichia coli.
- Partial purification and characterization of an escherichia coli toxic factor that induces morphological cell alterations.
- Purification and partial characterization of heat-stable enterotoxin of enterotoxigenic Escherichia coli.
- Individual and synergistic effects of rabbit granulocyte proteins on Escherichia coli.
- Partial purification of glycerophosphate acyltransferase from Escherichia coli.