Q Li1, X Xiao, F Wang. 1. Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen, China.
Abstract
AIMS: To find genes involved in chitinase production in chitinolytic bacterium Aeromonas caviae CB101. METHODS AND RESULTS: By transposome mutagenesis, a high-quality mutant library containing around 20,000 insertion mutants was constructed in A. caviae CB101. Mutants with higher, lower and delayed chitinase-producing abilities were identified and analysed further. Genomic sequences flanking the insertion sites of these mutants were amplified by thermal asymmetric interlaced-PCR, cloned and sequenced. The mutated genes involved in chitinase production and/or secretion in CB101 include (i) nagA and nagB gene homologues that are related to the metabolism of the chitin digestion product GlcNAc; (ii) ftsX and exeL gene homologues that are related to transport or secretion systems; (iii) varA and rpoH gene homologues that are related to transcriptional regulator sequences; (iv) other genes with unknown functions. CONCLUSIONS: Transposome mutagenesis is an efficient method to identify genes involved in the chitinase production in CB101. Chitinase production in CB101 is a complex system, and genes with various functions were identified in this study. SIGNIFICANCE AND IMPACT OF THE STUDY: Understanding regulation of chitinase production in CB101 would make molecular engineering of the bacterium for higher enzyme production possible.
AIMS: To find genes involved in chitinase production in chitinolytic bacterium Aeromonas caviae CB101. METHODS AND RESULTS: By transposome mutagenesis, a high-quality mutant library containing around 20,000 insertion mutants was constructed in A. caviae CB101. Mutants with higher, lower and delayed chitinase-producing abilities were identified and analysed further. Genomic sequences flanking the insertion sites of these mutants were amplified by thermal asymmetric interlaced-PCR, cloned and sequenced. The mutated genes involved in chitinase production and/or secretion in CB101 include (i) nagA and nagB gene homologues that are related to the metabolism of the chitin digestion product GlcNAc; (ii) ftsX and exeL gene homologues that are related to transport or secretion systems; (iii) varA and rpoH gene homologues that are related to transcriptional regulator sequences; (iv) other genes with unknown functions. CONCLUSIONS: Transposome mutagenesis is an efficient method to identify genes involved in the chitinase production in CB101. Chitinase production in CB101 is a complex system, and genes with various functions were identified in this study. SIGNIFICANCE AND IMPACT OF THE STUDY: Understanding regulation of chitinase production in CB101 would make molecular engineering of the bacterium for higher enzyme production possible.
Authors: Jannik Fonager; Blandine M D Franke-Fayard; John H Adams; Jai Ramesar; Onny Klop; Shahid M Khan; Chris J Janse; Andrew P Waters Journal: BMC Genomics Date: 2011-03-20 Impact factor: 3.969