Molecular and biochemical studies of some yeast strains

Abstract

This work focuses on detecting the level of polymorphisms among eleven KSA and Egyptian yeast strains, as efficient tools to assess the genetic relationships and development of yeast strain-specific molecular fingerprints. Moreover, estimation of the amino acid concentration was efficient in selecting the protein rich strains for animal feeding source. To detect the polymorphism among the yeast strains at the molecular level, 8 random amplified polymorphic DNA (RAPD), 5 inter simple sequence repeat (ISSR), and 8 specific simple sequence repeat (SSR) pair of primers were used. The total number of fragments produced by RAPD primers was 46 fragments and represented 52% of polymorphism. Also, number of fragments produced by ISSR and SSR primers was 45 fragments and recorded 63 and 77% of polymorphism among the strains, respectively. The amino acid analysis showed that yeast strains, Rhodotorula glutinis (Y.1); Schwanniomyces occidentalis (Y.2); Debaryomyces hansenii (Y.8); Kluyveromyces lactis (Y.9) and Pichia jadinii (Y.10) contained almost double the amount of total amino acids compared to the rest of the eleven strains used. The different molecular markers have confirmed each other and supported the biochemical analysis data, because the clustering  analysis has shown that the previous five strains, (Y.1); (Y.2); (Y.8); (Y.9) and (Y.10), were falling together in the same sub cluster.

Key words: Yeast, molecular markers, biochemical analysis.