比较基因组揭示广西酸菜乳杆菌碳水化合物活性酶谱

Comparative genome analysis of carbohydrate activity enzymes zymogram of Lactobacillus from Guangxi pickle

微生物中的碳水化合物活性酶(carbohydrate active enzymes,CAZymes)具有降解植物组织的作用,相对于真菌,目前对于乳杆菌的CAZymes研究还比较少。该研究从广西酸菜中筛选获得了3株产CAZymes的乳杆菌,并通过二代测序技术比较其编码基因。16S rRNA测序结果表明3株乳杆菌分别是Lactobacillus brevis DC4,Lactobacillus plantarum GLKK1和GLKK2;经液态发酵后,L.brevis DC4产果胶酶、纤维素酶和半纤维素酶分别为(0.40±0.01)、(0.04±0.01)和(0.19±0.01)U/mL。乳杆菌DC4、GLKK1和GLKK2编码序列分别有2615、3355以及3270个,COG注释均集中在碳水化合物转运与代谢、转录、氨基酸转运与代谢等;CAZymes注释均集中在糖苷水解酶(glycoside hydrolases,GHs)、糖基转移酶(glycosyl transferases,GTs)和碳水化合物酯酶(carbohydrate esterases,CEs)。3株乳杆菌包含17种CAZymes共有基因,包括纤维素、半纤维素、果胶、淀粉水解酶和酯酶。此外,L.brevis DC4菌株有10种特有基因,包括GH8、GH30和GH51家族,而L.plantarum GLKK1和L.plantarum GLKK2包含7种特有基因,包括GH39、GH13、CE2和GH78家族。

Carbohydrate active enzymes(CAZymes)in microorganisms can degrade plant tissues.Compared with fungi CAZymes,the research on Lactobacillus CAZymes is still relatively scarce.In this study,three lactobacillus strains producing CAZymes were isolated from Guangxi pickle,and their encoding genes were compared by second-generation sequencing.16S rRNA sequencing showed that these three strains were Lactobacillus brevis DC4,Lactobacillus plantarum GLKK1 and GLKK2.Under liquid-state fermentation,the activities of pectinase,cellulase and hemicellulase of L.brevis DC4 reached(0.40±0.01),(0.04±0.01),and(0.19±0.01)U/mL,respectively.The number of coding sequences(CDS)of DC4,GLKK1 and GLKK2 were 2615,3355 and 3270,respectively.According to COG annotations,they participated in carbohydrate transport and metabolism,transcription,amino acid transport and metabolism,and so on;CAZymes annotations focused on glycoside hydrolases(GHs),glycosyl transferases(GTs)and carbohydrate esterases(CEs).The three strains contained 17 CAZymes common genes,including cellulase,hemicellulase,pectinase and starch hydrolase and esterase.In addition,L.brevis DC4 contained 10 unique genes,including GH8,GH30 and GH51 families,and L.plantarum GLKK1 and L.plantarum GLKK 2 contained seven unique genes,including GH39,GH13,CE2 and GH78 families.