INTRODUCTION Most of pathogenesis related (PR) proteins possess complicated structures; hence their active recombinant forms are usually produced in eukaryotic systems. In this study, we employed an insect cell line to express a recombinant form of a previously identified grape PR3 allergen categorised as class IV chitinase. METHODS Grape chitinase cDNA was amplified by RT-PCR and inserted in...

Malaria parasites (ookinetes) appear to digest the peritrophic membrane in the mosquito midgut during penetration. Previous studies demonstrated that lectins specific for N-acetylglucosamine bind to the peritrophic membrane and proposed that the membrane contains chitin [Rudin, W. & Hecker, H. (1989) Parasitol. Res. 75, 268-279]. In the present study, we show that the peritrophic membrane is di...

Entomopathogenic fungi can produce a series of chitinases, some of which act synergistically with proteases to degrade insect cuticle. However, chitinase involvement in insect fungus pathogenesis has not been fully characterized. In this paper, an endochitinase, Bbchit1, was purified to homogeneity from liquid cultures of Beauveria bassiana grown in a medium containing colloidal chitin. Bbchit1...

Expression of the Arabidopsis acidic chitinase promoter was investigated during plant development and in response to inoculation with fungal pathogens. A chimeric gene composed of 1129 bp of 5[prime] upstream sequence from the acidic chitinase gene was fused to the [beta]-glucuronidase (GUS) coding region and used to transform Arabidopsis and tomato. Promoter activity was monitored by histochem...

Chitinases are the hydrolytic enzymes which protect plants against pathogen attack. However, the precise role of chitinases in disease resistance has not been explored in wheat. In the present study, in silico approach, including secondary structure analysis, detailed signature pattern study, cis-acting regulatory elements survey, evolutionary trends and three-dimensional molecular modeling was...

A new chitinase isozyme (Chitinase A), which had only one optimum pH toward a long substrate, glycolchitin, was purified from the peel of yam tuber by CTAB (hexadecyl trimethyl ammonium bromide) treatment and ammonium sulfate fractionation, followed by column chromatography on DEAE-Cellulofine A-500, chromatofocusing, and gel filtration on Sephacryl S-100. The molecular weight was 28,000 by SDS...

Chitinases (EC 3.2.1.14) are hydrolytic enzymes found in different organisms. In plants, they have been described in different tissues and organs, including seeds. This study was triggered by the isolation of a 30-kDa thermostable chitinase from Adenanthera pavonina L. seeds. The enzyme was submitted to N-terminal amino acid sequencing, and the analysis revealed a high degree of homology with c...

Fish express two different chitinases, acidic fish chitinase-1 (AFCase-1) and acidic fish chitinase-2 (AFCase-2), in the stomach. AFCase-1 and AFCase-2 have different degradation patterns, as fish efficiently degrade chitin ingested as food. For a comparison with the enzymatic properties and the primary structures of chitinase isozymes obtained previously from the stomach of demersal fish, in t...

Based on first principles and molecular mechanics calculations, we conclude that the mechanism of hevamine (a family 18 chitinase) involves an oxazoline ion intermediate stabilized by the neighboring C2' acetamido group. In this intermediate, the acetamido carbonyl oxygen atom forms a covalent bond to C1' of N-acetyl-glucosamine and has a transferred positive charge from the pyranose ring onto ...