Purification and Characterization of a Liver Chitinase from Golden Cuttlefish, Sepia esculenta

Distribution of Chitinolytic Enzymes in the Organs and cDNA Cloning of Chitinase Isozymes from the Stomach of Two Species of Fish, Chub Mackerel (<i>Scomber japonicus</i>) and Silver Croaker (<i>Pennahia argentata</i>)

“…Our laboratory has been investigating the purification, characteristics, and cDNA cloning of chitinases by using various samples, including fish (osteichthyes [17] [28]- [30] and chondrichthyes [18]), mollusca [20] [21], and crustacea [31]. We purified chitinase isozymes that function at acidic pH and are involved in digestion from the stomachs of osteichthyes [28]- [30].…”

Distribution of Chitinolytic Enzymes in the Organs and cDNA Cloning of Chitinase Isozymes from the Liver of Golden Cuttlefish <i>Sepia esculenta</i>

“…Using a chitin affinity column, CBPs were separated from the enzyme solution CBP-B was considered to be SeChi, which is a chitinase purified from the liver of S. esculenta [31], because the molecular weight of CBP-B (62 kDa) was consistent with that of SeChi. Two types of chitinase isozymes with molecular weights of 38 [28] and 42 kDa [30] have previously been purified from the liver of Japanese common squid.…”

“…Conversely, studies reporting the cDNA cloning and expression of chitinases and chitinase-like proteins from bivalves and gastropods, which are mollusks, have noted that these play roles in shell formation [20] [21] [22], immunity [23] [24] [25] [26], and digestion [27]. Chitinase isozymes have been purified and studied from the liver of Decembrachiata (squid and cuttlefish), and are involved in digestion [28] [29] [30] [31]. Furthermore, two chitinase isozymes have been reported in the liver of Japanese common squid, and identified based on differences in molecular weight and N-terminal amino acid sequences [29] [30], and two chitinase isozymes have been reported in the liver of spear squid, and identified based on expressed sequence tag (EST) analysis [32].…”

“…We have previously reported the distribution of chitinase activity using glycolchitin as the substrate [37] and purification and properties of a chitinase obtained from the liver of S. esculenta [31]; however, no findings of enzyme proteins and genes corresponding with the chitinase isozymes have been reported. In this study, we first observed the distribution of chitinase activity using two kinds of chitinase specific substrates in the body of S. esculenta, and isolated two types of chitin-binding proteins (CBPs) from the liver that exhibited particularly high chitinase activity.…”

Molecular Cloning of a Chitinase Gene from the Ovotestis of Kuroda’s Sea Hare <i>Aplysia kurodai</i>

“…The stomach chitinases of fish have been identified and are classified into two groups, acidic fish chitinase-1 (AF-Case-1) and acidic fish chitinase-2 (AFCase-2) based on the differences in their primary structure and the activity toward short substrates [8]. Chitinases from molluscs play important physiological roles in the digestion of food [10] [11], attacking crustaceans [12], and shell formation [13] [14]. However, reports on the distribution, characterization, and cDNA cloning of molluscan chitinases are limited [10]- [16].…”