Background
Mannanase is an enzyme that can catalyze random hydrolysis of beta-1,4-mannosidic linkages in the main chain of mannans, glucomannans and galactomannans which are the key polymers in hemicellulose. It has been used in a number of different industrial applications including food, feed, pharmaceutical, pulp/paper industries, and second generation biofuel. To optimize the expression system of mannanase Man23 gene, two kinds of vectors and host bacteria were determined and compared.
Conclusions
Mannanase is an important industrial enzyme and combination of vector pHY-p43 and host Brevibacillus brevis is a novel expression system for a mannanase decoding gene. This work aims at exploring a better expression system of mannanase Man23 decoding gene for industrial application.
Results
Recombinants pHY-p43-man23 and pBPS-man23 were constructed and transferred into Bacillus subtilis WB600 and Brevibacillus brevis respectively. For mannanase Man23 gene, recombinant pHY-p43-man23 expressed in Brevibacillus brevis had higher production and activity. Compared to the wild-type Bacillus subtilis B23, the production of recombinant pHY-p43-man23 in B. brevis increased by 10 times and activity increased by 21.3%. pHY-p43-man23 in B. brevis had activity at the range of 20 ~ 70 °C but its optimum temperature was 50 °C and had activity from pH 4 ~ 10 but its optimum pH was around 7. This demonstrated the recombinant had improved stability as well. Conclusions: Mannanase is an important industrial enzyme and combination of vector pHY-p43 and host Brevibacillus brevis is a novel expression system for a mannanase decoding gene. This work aims at exploring a better expression system of mannanase Man23 decoding gene for industrial application.