Production and Screening of High Yield Avermectin B1b Mutant of Streptomyces avermitilis 41445 Through Mutagenesis.

Content Provider	Europe PMC
Author	Siddique, Samia Syed, Quratulain Adnan, Ahmad Qureshi, Fahim Ashraf
Copyright Year	2014
Abstract	Background:Secondary metabolite production from wild strains is very low for economical purpose therefore certain strain improvement strategies are required to achieve hundred times greater yield of metabolites. Most important strain improvement techniques include physical and chemical mutagenesis. Broad spectrum mutagenesis through UV irradiation is the most important and convenient physical method.Objectives:The present study was conducted for enhanced production of avermectin B1b from Streptomyces avermitilis 41445 by mutagenesis using ultraviolet (UV) radiation, ethidium bromide (EB), and ethyl methanesulfonate (EMS) as mutagens.Materials and Methods:S. avermitilis DSM 41445 maintained on yeast extract malt extract glucose medium (YMG) was used as inoculum for SM2 fermentation medium. Spores of S. avermitilis DSM 41445 were exposed to UV radiation for physical broad spectrum mutagenesis and to EMS and EB for chemical mutagenesis. For each mutagen, the lethality rate and mutation rate were calculated along with positive mutation rate.Results:Avermectin B1b-hyper-producing mutant, produced using these three different methods, was selected according to the HPLC results. The mutant obtained after 45 minutes of UV radiation to the spores of S. avermitilis 41445, was found to be the best mutant for the enhanced production of avermectin B1b component (254.14 mg/L). Other avermectin B1b-hyper-producing mutants, were obtained from EMS (1 µL/mL) and EB (30 µL/mL) treatments, and yielded 202.63 mg/L and 199.30 mg/L of B1b, respectively.Conclusions:The hereditary stability analysis of the UV mentioning 45 minutes revealed the UV exposure time for mutants and 3 represented the colony taken from the plate irradiated for 45 minutes mutant showed that the production of avermectin B1b remained constant and no reverse mutation occurred after 15 generations.
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ISSN	20083645
Journal	Jundishapur Journal of Microbiology [Jundishapur J Microbiol]
Volume Number	7
DOI	10.5812/jjm.8626
PubMed Central reference number	PMC4138686
Issue Number	2
PubMed reference number	25147669
e-ISSN	20084161
Language	English
Publisher	Kowsar
Publisher Date	2014-02-01
Access Restriction	Open
Rights License	This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Copyright © 2014, Ahvaz Jundishapur University of Medical Sciences; Published by Kowsar Corp.
Subject Keyword	Avermectin B1b Mutagenesis Streptomyces avermitilis Submerged Fermentation Hereditary Stability
Content Type	Text
Resource Type	Article
Subject	Infectious Diseases Microbiology Microbiology (medical)