Construction of Interspecific Hybrids detween Aspergillus spp. by Nuclear transfer

수종의 Aspergillus 속 균 사이의 핵전이에 의한 종간잡종 형성

  • 노형선 (충남대학교 자연과학대학 미생물학과) ;
  • 이정애 (충남대학교 자연과학대학 미생물학과) ;
  • 이영하 (충남대학교 자연과학대학 미생물학과) ;
  • 김진미 (충남대학교 자연과학대학 미생물학과) ;
  • 정재훈 (한국과학기술연구원 생물공학과) ;
  • 맹필재 (충남대학교 자연과학대학 미생물학과)
  • Published : 1991.03.01

Abstract

Interspecific hybrids between the ASpergillus spp., A. awamori, A. usamii and A. oryzae, were obtained by nuclear transfer technique. Nuclei isolated from an auxotrophic mutant strain were transferred into the protoplasts of a recipient strain of different species. The frequency of interspecific hybrid formation by nuclear transfer was $2*10^{-5}$ $-7*10^{-4}$ In contrast, no interspecific hybrid was isolated by protoplast fusion. Among the hybrids tested, 10 strains showed increased activity of some or all components of cellulases, xylanases and amylase up to more than two times. Isozyme pattern of the hybrids were analyzed by polyacrylamide gel electrophoresis and isoelectric focusing followed by activity staining, which showed that some of the hybrids have isozyme patterns unidentical to either of the two parents. By measuring the DNA contents and the sizes ofthe conidia, the karyotypes of the hybrids were estimated to be aneuploid near to haploid, diploid or triploid. It was concluded that the unclear transfer technique is much more efficient in the formation of interspecific hybrids than protoplast fusion and is very useful for the improvement of Aspergillus strains.

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