Department of Agriculture Chemistry, Institute of Agricultural Science and Technology, Chonnam National University, Gwangju 500-757, Korea.
Mar Drugs. 2010 Jan 14;8(1):24-46. doi: 10.3390/md8010024.
Chitin deacetylases, occurring in marine bacteria, several fungi and a few insects, catalyze the deacetylation of chitin, a structural biopolymer found in countless forms of marine life, fungal cell and spore walls as well as insect cuticle and peritrophic matrices. The deacetylases recognize a sequence of four GlcNAc units in the substrate, one of which undergoes deacetylation: the resulting chitosan has a more regular deacetylation pattern than a chitosan treated with hot NaOH. Nevertheless plain chitin is a poor substrate, but glycolated, reprecipitated or depolymerized chitins are good ones. The marine Vibrio sp. colonize the chitin particles and decompose the chitin thanks to the concerted action of chitinases and deacetylases, otherwise they could not tolerate chitosan, a recognized antibacterial biopolymer. In fact, chitosan is used to prevent infections in fishes and crustaceans. Considering that chitin deacetylases play very important roles in the biological attack and defense systems, they may find applications for the biological control of fungal plant pathogens or insect pests in agriculture and for the biocontrol of opportunistic fungal human pathogens.
壳聚糖脱乙酰酶存在于海洋细菌、几种真菌和一些昆虫中,可催化壳聚糖的脱乙酰反应。壳聚糖是一种结构生物聚合物,存在于无数种海洋生物、真菌细胞壁和孢子、昆虫外骨骼和围食膜中。脱乙酰酶识别底物中四个 GlcNAc 单元的序列,其中一个单元发生脱乙酰反应:由此产生的壳聚糖比用热 NaOH 处理的壳聚糖具有更规则的脱乙酰模式。然而,普通壳聚糖是一种较差的底物,但经过糖基化、再沉淀或解聚的壳聚糖则是较好的底物。海洋弧菌通过壳聚糖酶和脱乙酰酶的协同作用来定殖壳聚糖颗粒并分解壳聚糖,否则它们无法耐受壳聚糖,因为壳聚糖是一种公认的抗菌生物聚合物。事实上,壳聚糖被用于预防鱼类和甲壳类动物的感染。鉴于壳聚糖脱乙酰酶在生物攻击和防御系统中发挥着非常重要的作用,它们可能在农业中用于真菌植物病原体或昆虫害虫的生物防治,以及用于机会性真菌人类病原体的生物防治。