Characterization of the novel antifungal chitosanase PgChP and the encoding gene from Penicillium chrysogenum

Abstract

The protein PgChP is a new chitosanase produced by Penicillium chrysogenum AS51D that showed antifungal activity against toxigenic molds. Two isoforms were found by SDS-PAGE in the purified extract of PgChP. After enzymatic deglycosylation, only the smaller isoform was observed by SDS-PAGE. Identical amino acid sequences were obtained from the two isoforms. Analysis of the molecular mass by electrospray ionization-mass spectrometry revealed six major peaks from 30 to 31 kDa that are related to different levels of glycosylation. The pgchp gene has 1,146 bp including four introns and an open reading frame encoding a protein of 304 amino acids. The translated open reading frame has a predicted mass of 32 kDa, with the first 21 amino acids comprising a signal peptide. Two N glycosylation consensus sequences are present in the protein sequence. The deduced sequence showed high identity with fungal chitosanases. A high level of catalytic activity on chitosan was observed. PgChP is the first chitosanase described from P. chrysogenum. Given that enzymes produced by this mold species are granted generally recognized as safe status, PgChP could be used as a food preservative against toxigenic molds and to obtain chitosan oligomers for food additives and nutraceuticals.

Genome sequence of the necrotrophic fungus Penicillium digitatum, the main postharvest pathogen of citrus

“…These cationic proteins share the previously described γ-motif common to small antimicrobial proteins and peptides [44]. Two distinct antifungal CRPs have been isolated and characterized from cultures of P. chrysogenum [45,46]. Among the predicted proteins in P. digitatum we found a CRP (PDIG_68840) showing 91% amino acid identity with the Pc12g08290 gene from P. chrysogenum which corresponds to one of the previously reported proteins [46].…”

Genomic characteristics and comparative genomics analysis of Penicillium chrysogenum KF-25

“…SRP plays a critical role in targeting of secretory proteins to the cellular membrane [25], while the Sec secretion system is responsible for protein translocation across the cytoplasmic membrane [26]. P. chrysogenum has been widely used to produce penicillin and some other secondary metabolites with antimicrobial activity [2,7-9,27,28]. The secretory system and transporters are essential for secretion of these antimicrobial substances and for import of their substrates.…”

“…In addition to producing penicillin, P. chrysogenum has exhibited abilities in others areas, including bioleaching, biological remediation, promoting plant growth, and producing non-β-lactam antibiotics and antifungal agents [2-6]. According to previous reports, several P. chrysogenum strains produce secreted proteins, such as PAF, PgAFP, and PgChP, which inhibit the growth of opportunistic zoopathogens, plant-pathogenic fungi, and toxigenic molds [7-9]. With their high stability, effective inhibitory activity, and broad inhibition spectra, these three proteins could be effective antifungal agents in medicine and agriculture [10,11].…”

Cloning and overexpression of a new chitosanase gene from Penicillium sp. D-1

“…Up to now, other reported Penicillium strains which could produce chitosanase were P. islandicum , P. spinulosum and P. chrysogenum (Fenton and Eveleigh, 1981; Ak et al ., 1998; Rodríguez-Martín et al, 2010). …”