BmSI-7, a novel subtilisin inhibitor from Boophilus microplus, with activity toward Pr1 proteases from the fungus Metarhizium anisopliae.
BmSI-7 and BmSI-6, two Boophilus microplus subtilisin inhibitors (BmSI) were purified and characterized from eggs. The inhibitors isolated by classical purification methods presented molecular masses of 7408 and 7271Da, respectively, by MALDI-TOF-MS. Both BmSI-7 and BmSI-6 inhibited neutrophil elastase (K(i) 0.4 and 0.3nM) and subtilisin A (K(i) 1.4nM for both inhibitors). They also strongly inhibited Pr1 proteases from the fungus Metarhizium anisopliae; BmSI-7 (K(i) 50nM) and BmSI-6 (K(i) 2.2nM). The BmSI-7 full length cDNA was obtained using amino acid sequence information of BmSI-7 peptides generated by proteolytic digestion. BmSI-7 belongs to trypsin inhibitor like cysteine rich domain family (TIL), and it is transcribed in ovary, fat body, gut, salivary gland and haemocytes. BmSI-7 is the first TIL inhibitor described with inhibitory activity toward subtilisin A and Pr1 proteases of entomopathogenic fungi.
Sasaki
Sergio D
SD
Departamento de Bioquímica, UNIFESP-EPM, Rua 3 de Maio, 100, 04044-020 São Paulo, SP, Brazil.
de Lima
Cássia A
CA
Lovato
Diogo V
DV
Juliano
Maria A
MA
Torquato
Ricardo J S
RJ
Tanaka
Aparecida S
AS
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002845:Chromatography / Q000379:methods; D018076:DNA, Complementary / Q000737:chemistry; D005260:Female; D005656:Fungal Proteins / Q000037:antagonists & inhibitors*; D026863:Ixodidae / Q000737:chemistry*; D052981:Metarhizium / Q000187:drug effects / Q000201:enzymology*; D008969:Molecular Sequence Data; D053491:Proteinase Inhibitory Proteins, Secretory / Q000494:pharmacology; D012697:Serine Endopeptidases; D015842:Serine Proteinase Inhibitors / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D020860:Subtilisin / Q000037:antagonists & inhibitors*
D018076:DNA, Complementary; D005656:Fungal Proteins; D053491:Proteinase Inhibitory Proteins, Secretory; D015842:Serine Proteinase Inhibitors; D012697:Serine Endopeptidases; C093192:pr1 protein, Metarhizium anisopliae; D020860:Subtilisin