Related Experiment Video
Updated: Oct 12, 2026
Genetic Engineering of an Unconventional Yeast for Renewable Biofuel and Biochemical Production
Published on: September 20, 2016
Molecular characterization of Yarrowia lipolytica and Candida zeylanoides isolated from poultry
1Center for Food Safety and Quality Enhancement, University of Georgia, Griffin, Georgia 30223-1797, USA.
Abstract:
Yeast isolates from raw and processed poultry products were characterized using PCR amplification of the internally transcribed spacer (ITS) 5.8S ribosomal DNA region (ITS-PCR), restriction analysis of amplified products, randomly amplified polymorphic DNA (RAPD) analysis, and pulsed-field gel electrophoresis (PFGE). ITS-PCR resulted in single fragments of 350 and 650 bp, respectively, from eight strains of Yarrowia lipolytica and seven strains of Candida zeylanoides. Digestion of amplicons with HinfI and HaeIII produced two fragments of 200 and 150 bp from Y. lipolytica and three fragments of 350, 150, and 100 bp from C. zeylanoides, respectively. Although these fragments showed species-specific patterns and confirmed species identification, characterization did not enable intraspecies typing. Contour-clamped heterogeneous electric field PFGE separated chromosomal DNA of Y. lipolytica into three to five bands, most larger than 2 Mbp, whereas six to eight bands in the range of 750 to 2,200 bp were obtained from C. zeylanoides. Karyotypes of both yeasts showed different polymorphic patterns among strains. RAPD analysis, using enterobacterial repetitive intergenic sequences as primers, discriminated between strains within the same species. Cluster analysis of patterns formed groups that correlated with the source of isolation. For ITS-PCR, extraction of DNA by boiling yeast cells was successfully used.
Insights
Molecular techniques like PCR and PFGE were used to identify yeast strains from poultry. Randomly amplified polymorphic DNA (RAPD) analysis proved effective for differentiating strains within species, correlating with their origin.
Area of Science:
- Microbiology
- Molecular Biology
- Food Science
Background:
- Yeast contamination in poultry products poses food safety concerns.
- Accurate identification and strain typing of yeasts are crucial for tracking sources and preventing outbreaks.
Purpose of the Study:
- To characterize yeast isolates from raw and processed poultry.
- To evaluate the efficacy of various molecular methods for yeast identification and intraspecies typing.
Main Methods:
- Internally transcribed spacer (ITS) PCR and restriction fragment length polymorphism (RFLP).
- Contour-clamped homogeneous electric field pulsed-field gel electrophoresis (CHEF-PFGE).
- Randomly amplified polymorphic DNA (RAPD) analysis using enterobacterial repetitive intergenic sequences.
Main Results:
- ITS-PCR and RFLP confirmed species identification of Yarrowia lipolytica and Candida zeylanoides but lacked intraspecies discriminatory power.
- CHEF-PFGE revealed polymorphic karyotypes among strains of both yeast species.
- RAPD analysis successfully discriminated between strains within the same species, with cluster analysis correlating strain patterns to their isolation source.
Conclusions:
- RAPD analysis is a valuable tool for intraspecies typing of yeasts from poultry products.
- Molecular techniques, particularly RAPD, aid in understanding yeast population dynamics and contamination sources in the food industry.
More Related Videos
07:24A Hybrid DNA Extraction Method for the Qualitative and Quantitative Assessment of Bacterial Communities from Poultry Production Samples
Published on: December 10, 2014
10:33Multi-locus Variable-number Tandem-repeat Analysis of the Fish-pathogenic Bacterium Yersinia ruckeri by Multiplex PCR and Capillary Electrophoresis
Published on: June 17, 2019