Wenwen Zhang1, Zhaohui Chen1, Mengmeng Wu1, Zhong Shi1, Feng Zhu1, Guoqiang Li1, Ting Ma2. 1. Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China. 2. Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China. tingma@nankai.edu.cn.
Abstract
OBJECTIVE: To improve the production of welan gum and obtain a carotenoid-free strain while reducing the fermentation and post-treatment costs. RESULTS: The vitreoscilla globin (vgb) gene combined with the β-galactosidase (lacZ) promoter was inserted into the phytoene synthase (crtB) gene region of the chromosome in Alcaligenes sp. ATCC31555. When the recombinant strain was grown in a 5 l fermentor, welan gum was produced at 24 ± 0.4 g l(-1) compared to 21 g ± 0.4 g l(-1) in the wild type. Furthermore, the carotenoid-free welan gum produced using Alcaligenes sp. ATCC31555 VHb strain was less expensive with improved properties. CONCLUSIONS: Alcaligenes sp. ATCC31555 VHb strain was a better neutral welan-producing strain with a higher production than the wild-type strain.
OBJECTIVE: To improve the production of welan gum and obtain a carotenoid-free strain while reducing the fermentation and post-treatment costs. RESULTS: The vitreoscilla globin (vgb) gene combined with the β-galactosidase (lacZ) promoter was inserted into the phytoene synthase (crtB) gene region of the chromosome in Alcaligenes sp. ATCC31555. When the recombinant strain was grown in a 5 l fermentor, welan gum was produced at 24 ± 0.4 g l(-1) compared to 21 g ± 0.4 g l(-1) in the wild type. Furthermore, the carotenoid-free welan gum produced using Alcaligenes sp. ATCC31555 VHb strain was less expensive with improved properties. CONCLUSIONS:Alcaligenes sp. ATCC31555 VHb strain was a better neutral welan-producing strain with a higher production than the wild-type strain.