Document Type

Honors Project

First Advisor

Dr. Stephen Baron

Degree Award Date

Spring 4-30-2022


Polyhydroxybutyrate (PHB), PHB depolymerase, phaZ, Streptomyces sp. SFB5A; bld mutants, plastic, PCR, gel electrophoresis


Environmental Microbiology and Microbial Ecology


In an effort to reduce plastic waste, there has been interest in the development of biodegradable plastics. One group of biodegradable plastics that has sparked the interest of many biologists is polyhydroxybutyrate (PHB), which can be broken down by PHB depolymerase. Wild-type strains of Streptomyces sp. SFB5A produce PHB depolymerase, but bald mutants of this species do not. This indicates that there is a mutation within the PHB depolymerase gene, phaZ, in the bald mutants. In order to identify where these mutations lie in the bld mutants, the goal of this project is to amplify the phaZ gene from the bld4, bld10, and bld15 mutants using polymerase chain reaction (PCR), visualize PCR products using gel electrophoresis, and sequence products to determine if any mutations are present in the promoter or coding regions. Mutations identified in the bald mutants will hopefully lead to the identification of where the production of PHB depolymerase is regulated.

Recommended Citation

Young, Britney. “Identification of Mutations in the phaZ Gene of Bald Mutants of Streptomyces sp. SFB5A.” Senior Honors Projects, Bridgewater College, 2021.