Weiling Lin1,2, Xiaohong Xu3, Ruirui Lv1, Wei Huang1,4, Hafeez Ul Haq1, Yuanyuan Gao1, Hongli Ren1, Canhua Lan1, Baoyu Tian5. 1. Engineering Research Center of Industrial Microbiology of Ministry of Education, College of Life Sciences, Fujian Normal University, No.8, Shangsan Road, Cangshan District, Fuzhou, 350108, Fujian, China. 2. Fujian Health College, Fuzhou, 350101, Fujian, China. 3. Library, Fujian Normal University, Fuzhou, 350108, Fujian, China. 4. Institute of Agricultural Quality Standards and Testing Technology Research, Fujian Academy of Agricultural Sciences, Fuzhou, 350003, Fujian, China. 5. Engineering Research Center of Industrial Microbiology of Ministry of Education, College of Life Sciences, Fujian Normal University, No.8, Shangsan Road, Cangshan District, Fuzhou, 350108, Fujian, China. tianby@fjnu.edu.cn.
Abstract
OBJECTIVES: To reveal the potential mechanism and key determinants that contributed to the improved pectinase activity in Aspergillus niger mutant EIMU2, which was previously obtained by UV-mutagenesis from the wild-type A. niger EIM-6. RESULTS: Proteomic analysis for Aspergillus niger EIMU2 by two-dimensional electrophoresis demonstrated that mutant EIMU2 harbored a multiple enzyme system for the degradation of pectin, mainly constituting by main-chain-cleaving enzymes polygalacturonase, pectate lyase, pectinesterase, and some accessory enzymes rhamnogalacturonan lyase and arabinofuranosidase. Further quantitatively differential proteomic analysis revealed that the quantities of four proteins, pectinesterase, rhamnogalacturonan lyase A, DNA-directed RNA polymerase A, and a hypothetical protein in strain EIMU2 were much higher than those in EIM-6. PCR amplification, sequencing and alignment analysis of genes for the two main members of pectin-degrading enzymes, pectate lyase and polygalacturonase showed that their sequences were completely consistent in A. niger EIM-6 and mutant EIMU2. CONCLUSIONS: The result demonstrated that the improved pectinase activity by UV-mutagenesis in A. niger EIMU2 was probably contributed to the up-regulated expression of rhamnogalacturonan lyase, or pectinesterase, which resulted in the optimization of synergy amongst different components of pectin-degrading enzymes.
OBJECTIVES: To reveal the potential mechanism and key determinants that contributed to the improved pectinase activity in Aspergillus niger mutant EIMU2, which was previously obtained by UV-mutagenesis from the wild-type A. niger EIM-6. RESULTS: Proteomic analysis for Aspergillus niger EIMU2 by two-dimensional electrophoresis demonstrated that mutant EIMU2 harbored a multiple enzyme system for the degradation of pectin, mainly constituting by main-chain-cleaving enzymes polygalacturonase, pectate lyase, pectinesterase, and some accessory enzymes rhamnogalacturonan lyase and arabinofuranosidase. Further quantitatively differential proteomic analysis revealed that the quantities of four proteins, pectinesterase, rhamnogalacturonan lyase A, DNA-directed RNA polymerase A, and a hypothetical protein in strain EIMU2 were much higher than those in EIM-6. PCR amplification, sequencing and alignment analysis of genes for the two main members of pectin-degrading enzymes, pectate lyase and polygalacturonase showed that their sequences were completely consistent in A. niger EIM-6 and mutant EIMU2. CONCLUSIONS: The result demonstrated that the improved pectinase activity by UV-mutagenesis in A. niger EIMU2 was probably contributed to the up-regulated expression of rhamnogalacturonan lyase, or pectinesterase, which resulted in the optimization of synergy amongst different components of pectin-degrading enzymes.
Authors: Ebru Alazi; Tim Knetsch; Marcos Di Falco; Ian D Reid; Mark Arentshorst; Jaap Visser; Adrian Tsang; Arthur F J Ram Journal: Appl Microbiol Biotechnol Date: 2018-01-24 Impact factor: 4.813