Nejvíce citovaný článek - PubMed ID 15052274
Chitin, a polymer of N-acetyl-D-glucosamine (GlcNAc), is a major structural component in chitin-containing organism including crustaceans, insects and fungi. Mammals express two chitinases, chitotriosidase (Chit1) and acidic mammalian chitinase (AMCase). Here, we report that pig AMCase is stable in the presence of other digestive proteases and functions as chitinolytic enzyme under the gastrointestinal conditions. Quantification of chitinases expression in pig tissues using quantitative real-time PCR showed that Chit1 mRNA was highly expressed in eyes, whereas the AMCase mRNA was predominantly expressed in stomach at even higher levels than the housekeeping genes. AMCase purified from pig stomach has highest activity at pH of around 2-4 and remains active at up to pH 7.0. It was resistant to robust proteolytic activities of pepsin at pH 2.0 and trypsin and chymotrypsin at pH 7.6. AMCase degraded polymeric chitin substrates including mealworm shells to GlcNAc dimers. Furthermore, we visualized chitin digestion of fly wings by endogenous AMCase and pepsin in stomach extract. Thus, pig AMCase can function as a protease resistant chitin digestive enzyme at broad pH range present in stomach as well as in the intestine. These results indicate that chitin-containing organisms may be a sustainable feed ingredient in pig diet.
- MeSH
- chitin metabolismus MeSH
- chitinasy genetika izolace a purifikace metabolismus MeSH
- chymotrypsin metabolismus MeSH
- dieta * MeSH
- Drosophila chemie MeSH
- endopeptidasy metabolismus MeSH
- gastrointestinální trakt metabolismus MeSH
- křídla zvířecí chemie MeSH
- messenger RNA genetika metabolismus MeSH
- orgánová specificita MeSH
- pepsinogen A metabolismus MeSH
- prasata genetika MeSH
- rozpustnost MeSH
- substrátová specifita MeSH
- Tenebrio MeSH
- tkáňové extrakty MeSH
- trypsin metabolismus MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- chitin MeSH
- chitinasy MeSH
- chymotrypsin MeSH
- endopeptidasy MeSH
- messenger RNA MeSH
- pepsinogen A MeSH
- tkáňové extrakty MeSH
- trypsin MeSH