title: A newly isolated Paecilomyces sp. WSH-L07 for laccase production: isolation, identification, and production enhancement by complex inducement.
abstract: Laccase can catalyze the oxidation of a wide range of organic and inorganic substrates. In this study, an easily detectable method was employed for screening laccase-producing microorganisms by using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) as laccase-secretion indicator. A novel laccase-producing strain was isolated and identified as Paecilomyces sp. WSH-L07 according to the morphological characteristics and the comparison of internal transcribed spacer (ITS) ribosomal DNA (rDNA) gene sequences. In further investigation, the production of laccase by Paecilomyces sp. WSH-L07 was greatly enhanced by the nontoxic inducers of copper sulphate and methylene blue. Under the induction of 50 microM copper sulphate and 20 microM methylene blue, the maximum laccase production was obtained. When these inducers were added into cultivation medium at 24 h and 12 h, respectively, an increment of about 100 times of laccase activity compared with that of in inducer-free medium and about two times of that of in single copper-supplemented medium was observed. Compared with other Paecilomyces species, Paecilomyces sp. WSH-L07 exhibit the better laccase-producing characteristics with an activity of 1,650 U/l on the eighth day, suggesting its potential ability for industrial application.
authors.affiliation: Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 214122 Wuxi, Jiangsu, China.
authors.forename: Zhiyu
authors.initials: Z
authors.lastname: Liu
authors.forename: Dongxu
authors.initials: D
authors.lastname: Zhang
authors.forename: Zhaozhe
authors.initials: Z
authors.lastname: Hua
authors.forename: Jianghua
authors.initials: J
authors.lastname: Li
authors.forename: Guocheng
authors.initials: G
authors.lastname: Du
authors.forename: Jian
authors.initials: J
authors.lastname: Chen
mesh_terms: D052160:Benzothiazoles / Q000494:pharmacology; D019327:Copper Sulfate / Q000378:metabolism; D003470:Culture Media / Q000737:chemistry; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D020536:Enzyme Activators / Q000378:metabolism; D007202:Indicators and Reagents / Q000494:pharmacology; D042845:Laccase / Q000096:biosynthesis*; D008751:Methylene Blue / Q000378:metabolism; D008969:Molecular Sequence Data; D010143:Paecilomyces / Q000145:classification* / Q000201:enzymology* / Q000302:isolation & purification; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D013451:Sulfonic Acids / Q000494:pharmacology
chemical_list: D052160:Benzothiazoles; D003470:Culture Media; D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer; D020536:Enzyme Activators; D007202:Indicators and Reagents; D013451:Sulfonic Acids; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D042845:Laccase; D019327:Copper Sulfate; D008751:Methylene Blue