title: Modification of the C terminus of cecropin is essential for broad-spectrum antimicrobial activity.
abstract: Cecropin A is a naturally occurring peptide with bactericidal activity against gram-negative and gram-positive bacteria. Production of large quantities of bactericidal peptides that are similar in structure and activity to cecropin A has been achieved by combining recombinant DNA techniques and techniques and chemical modification. Expression of the bactericidal peptide in Escherichia coli was accomplished through the formation of a fusion protein. The 5' end of the L-ribulokinase gene was fused to a single copy of a synthetic gene encoding cecropin A. A methionine codon was engineered between the two genes, and a methionylglycine extension was introduced at the C terminus of cecropin A. Cyanogen bromide treatment of the fusion protein yielded cecropin A with a C-terminal homoserine. The recombinant cecropin A with a homoserine at the C terminus did not kill most gram-positive bacteria tested. However, recombinant cecropin A with a chemically modified C terminus has antimicrobial activity similar to that of cecropin produced by cecropia pupae.
authors.affiliation: XOMA Corp., Santa Monica, California 90404.
authors.forename: J E
authors.initials: JE
authors.lastname: Callaway
authors.forename: J
authors.initials: J
authors.lastname: Lai
authors.forename: B
authors.initials: B
authors.lastname: Haselbeck
authors.forename: M
authors.initials: M
authors.lastname: Baltaian
authors.forename: S P
authors.initials: SP
authors.lastname: Bonnesen
authors.forename: J
authors.initials: J
authors.lastname: Weickmann
authors.forename: G
authors.initials: G
authors.lastname: Wilcox
authors.forename: S P
authors.initials: SP
authors.lastname: Lei
mesh_terms: D000900:Anti-Bacterial Agents / Q000096:biosynthesis / Q000494:pharmacology*; D023181:Antimicrobial Cationic Peptides; D004274:DNA, Recombinant / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005029:Ethylenediamines / Q000494:pharmacology; D006094:Gram-Positive Bacteria / Q000187:drug effects; D007301:Insect Hormones / Q000096:biosynthesis / Q000235:genetics / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D010452:Peptide Biosynthesis; D010455:Peptides / Q000235:genetics / Q000494:pharmacology*; D010957:Plasmids / Q000235:genetics; D013329:Structure-Activity Relationship
chemical_list: D000900:Anti-Bacterial Agents; D023181:Antimicrobial Cationic Peptides; D004274:DNA, Recombinant; D005029:Ethylenediamines; D007301:Insect Hormones; D010455:Peptides; C031234:ethylenediamine; C031161:cecropin A