Primary structure of a new cysteine proteinase inhibitor from pig leucocytes

Abstract

The primary structure of a pig leucocyte cysteine proteinase inhibitor, also called cathelin, was determined. The sequence was obtained from analyses of peptides isolated from the chymotryptic, endoproteinase Lys-C and protease V8 digests, and by analysis of the peptides derived from the hydrolysis of the aspartyl-prolyl bond of the carboxymethylated inhibitor. The inhibitor consists of 96 residues. The N-terminal residue of the inhibitor is pyrrolidonecarboxylic acid. The amino acid sequence. of cathelin suggests the appearance of a new family of cysteine proteinase inhibitors.

Molecular cloning of a putative homolog of proline/arginine‐rich antibacterial peptides from porcine bone marrow

“…It has been suggested that all these proteins are members of a novel family of leukocyte proteins with antibacterial, LPS-binding and proteinase-inhibitory activities [8]. The N-terminal region is similar to the protein sequence of pig cathelin which had previously been isolated from pig blood leukocytes [9]. Therefore, it has been speculated that cathelin is the N-terminal fragment of a pig homolog of antibacterial peptides [8].…”

Cathelicidins: a novel protein family with a common proregion and a variable C‐terminal antimicrobial domain

“…The prosequence which is present in the precursors of these peptides is highly identical to the sequence of a protein termed cathelin. This protein was isolated from porcine leukocytes [40], and is likely to be the proregion of a processed precursor of this type, from which the C-terminal antimicrobial peptide has been released ( of precursors, and this term will be used herewith to indicate molecules with a cathelin-like proregion and a C-terminal antimicrobial domain. Several mismatches in the 5' regions indicate that, in general, cathelicidins do not originate by posttranscriptional processing.…”

Prophenin‐1, an exceptionally proline‐rich antimicrobial peptide from porcine leukocytes

“…Although these peptides show marked diversity in structure and antimicrobial spectrum, the precursors of many antibiotic peptides of porcine [2 6], bovine [7][8][9][10] and rabbit [11,12] origin contain a highly conserved preproregion that is homologous to cathelin, a putative cysteine-proteinase inhibitor originally isolated from pig leukocytes [13,14]. Several of these cathelin-associated peptides have been isolated and characterized, including porcine PR-39 [15] and protegrins PG-1, 2 and 3 [16]; bovine Bac 5 [17,18], indolicidin 9 [19] and cyclic dodecapeptide [20]; and rabbit p15 [12] and CAP 18 [11].…”