Yeast

About: Yeast is a research topic. Over the lifetime, 31777 publications have been published within this topic receiving 868967 citations. The topic is also known as: yeasts.

Cloning of yeast gene for trichodermin resistance and ribosomal protein L3.

Abstract: Yeast cells sensitive to the eukaryotic protein synthesis inhibitor trichodermin have been transformed with autonomously replicating recombinant plasmids carrying DNA fragments of the genome of a trichodermin-resistant yeast strain. After selection for trichodermin-resistant cells, several transformants yielded a plasmid containing a 13.5-kilobase (kb) DNA fragment that encodes the trichodermin resistance gene, tcm1, and the gene for ribosomal protein L3, the largest of the yeast ribosomal proteins. Cells carrying this plasmid are resistant to trichodermin and to the related drug verrucarin A as well as to the unrelated drug anisomycin. This pattern of resistance is similar to that exhibited by strains carrying a chromosomal copy of tcm1. Moreover, polyribosomes prepared from transformed cells are resistant to trichodermin when tested in an in vitro protein synthesis assay. Subcloning of the 13.5-kb DNA fragment revealed that the gene for tcm1 and the gene for protein L3 are contained within a 3.2-kb segment. These results suggest that the gene for trichodermin resistance in yeast specifies ribosomal protein L3.

Expression of two Trichoderma reesei endoglucanases in the yeast Saccharomyces cerevisiae.

Abstract: The cDNA copies of the two endo-beta-1,4-glucanase genes, egl1 and egl3, from the filamentous fungus Trichoderma reesei were expressed in yeast Saccharomyces cerevisiae under the control of the yeast phosphoglycerate kinase gene promoter. Active EGI and EGIII enzyme was produced and secreted by yeast into the growth medium. The recombinant EGI enzyme was larger and more heterogeneous in size than the native enzyme secreted by Trichoderma, due to differences in the extent of N-glycosylation between these two organisms. The morphology of the yeast cells producing EGI or EGIII was clearly different from control strain.

Purification of the yeast U4/U6.U5 small nuclear ribonucleoprotein particle and identification of its proteins.

Abstract: The yeast U4/U6⋅U5 pre-mRNA splicing small nuclear ribonucleoprotein (snRNP) is a 25S small nuclear ribonucleoprotein particle similar in size, composition, and morphology to its counterpart in human cells. The yeast U4/U6⋅U5 snRNP complex has been purified to near homogeneity by affinity chromatography and preparative glycerol gradient sedimentation. We show that there are at least 24 proteins stably associated with this particle and performed mass spectrometry microsequencing to determine their identities. In addition to the seven canonical core Sm proteins, there are a set of U6 snRNP specific Sm proteins, eight previously described U4/U6⋅U5 snRNP proteins, and four novel proteins. Two of the novel proteins have likely RNA binding properties, one has been implicated in the cell cycle, and one has no identifiable sequence homologues or functional motifs. The purification of the low abundance U4/U6⋅U5 snRNP from yeast and the powerful sequencing methodologies using small amounts of protein make possible the rapid identification of novel and previously unidentified components of large, low-abundance macromolecular machines from any genetically manipulable organism.