Generation of null alleles for the functional analysis of six genes from the right arm of Saccharomyces cerevisiae chromosome II

Using PCR‐ligated long flanking homology cassettes, null alleles of six open reading frames (ORFs) from chromosome II have been created in Saccharomyces cerevisiae. Deletants were constructed in three genetic backgrounds: FY1679, W303 and CEN.PK2. Tetrad analysis of heterozygous deletants revealed that none of the ORFs is essential for vegetative growth. Basic phenotypic analysis of haploid deletants showed that deletion of the YBR283c ORF causes a slight growth defect at 30°C and 37°C on glycerol‐complete, glucose‐complete, and glucose‐minimal media only in the FY1679 and W303 backgrounds. Transformation of these deletants with the corresponding cognate gene in a centromeric plasmid complements the defects. Deletion of the YBR287w ORF leads to poor growth on glucose‐minimal medium at 15°C in the FY1679 background. None of the six ORFs seems to be involved in mating or sporulation. Copyright © 1999 John Wiley & Sons, Ltd.     

乳液聚合竞聚率测定技术进展

将近年来测定共聚物的组成方法分为气相色谱法、红外色谱法、氢核磁共振法、元素分析法等4类。综述了Fineman Ross(F-R)法、Kelen Tudos(K-T)法和Yezreielv Brokhina Roskin(YBR)法等3种计算单体竞聚率方法的优缺点,展望了乳液聚合竞聚率研究技术的前景。