||The bioprocessing of chitinous fishery wastes (CFWs) to chitinases through fermentation
approaches has gained importance owing to its great benefits in reducing the enzyme production
cost, and utilizing chitin waste. In this work, our study of the chitinase production of Paenibacillus sp.
TKU052 in the presence of different kinds of CFWs revealed a preference for demineralized crab
shells powder (deCSP); furthermore, a 72 kDa chitinase was isolated from the 0.5% deCSP-containing
medium. The Paenibacillus sp. TKU052 chitinase displayed maximum activity at 70 ◦C and pH 4–5,
while Zn2+, Fe3+, Triton X-100, Tween 40, and SDS exerted a negative effect on its activity, whereas
Mn2+ and 2-mercaptoethanol were found to potentially enhance the activity. Among various kinds
of polysaccharide, Paenibacillus sp. TKU052 chitinase exhibited the best catalytic activity on colloidal
chitin (CC) with Km = 9.75 mg/mL and Vmax = 2.43 µmol/min. The assessment of the hydrolysis of
CC and N-acetyl chitooligosaccharides revealed that Paenibacillus sp. TKU052 chitinase possesses multiple catalytic functions, including exochitinase, endochitinase, and N-acetyl-β-D-glucosaminidase
activities. Finally, the combination of Paenibacillus sp. TKU052 chitinase and Streptomyces speibonae
TKU048 N-acetyl-β-D-glucosaminidase could efficiently convert CC to N-acetyl-D-glucosamine
(GlcNAc) with a production yield of 94.35–98.60% in 12–24 h.