Purification of chitinase/chitosanase from Bacillus cereus and discovery of an enzyme inhibitor.
A chitinase and a chitosanase were induced from a squid pen powder (SPP)-containing medium of Bacillus cereus TKU030 and purified by precipitation with ammonium sulphate and combined column chromatography. The purified chitinase and chitosanase exhibited optimum activity at 60 °C, pH 5-6 and 40 °C, pH 4, respectively. The chitinase and chitosanase were stable at 25-60 °C, pH 4-7 and 25-50 °C, pH 3-7, respectively. The chitinase and chitosanase showed the highest activity toward β-chitin and 60% DD chitosan, respectively. The chitinase was significantly inhibited by Mn(2+) and EDTA but activated by Cu(2+), Fe(2+) and Ca(2+). The chitosanase was significantly inhibited by Cu(2+), Fe(2+), Zn(2+), Mn(2+) and EDTA. The chitinase showed high stability in the presence of various surfactants, such as SDS, Tween 20, Tween 40 and Triton X-100. In contrast, these surfactants were inhibitors of the chitosanase. The chitinase and chitosanase were also inhibited by TKUPSP017, a small synthetic boron-containing molecule with a BF3K side-chain. However, TKUPSP017 enhanced the growth of B. cereus TKU030 in SPP-containing medium.
Life Science Development Center, Tamkang University, New Taipei City 25137, Taiwan; Department of Chemistry, Tamkang University, New Taipei City 25137, Taiwan. Electronic address: ltw27@ms55.hinet.net.
Tzu-Wen
TW
Liang
Department of Chemistry, Tamkang University, New Taipei City 25137, Taiwan.
Yue-Yin
YY
Chen
Department of Chemistry, Tamkang University, New Taipei City 25137, Taiwan.
Po-Shen
PS
Pan
Life Science Development Center, Tamkang University, New Taipei City 25137, Taiwan; Department of Chemistry, Tamkang University, New Taipei City 25137, Taiwan. Electronic address: sabulo@mail.tku.edu.tw.
San-Lang
SL
Wang
D001409:Bacillus cereus / Q000201:enzymology*; D002686:Chitin / Q000737:chemistry; D002688:Chitinases / Q000737:chemistry / Q000302:isolation & purification*; D048271:Chitosan / Q000737:chemistry; D004791:Enzyme Inhibitors / Q000737:chemistry; D006026:Glycoside Hydrolases / Q000737:chemistry / Q000302:isolation & purification*
D004791:Enzyme Inhibitors; D002686:Chitin; D048271:Chitosan; D006026:Glycoside Hydrolases; C019868:chitosanase; D002688:Chitinases
Bacillus cereus; Boron; Chitinase; Chitinase inhibitor; Chitosanase; Squid pen