Lohmann and Meyerhof first differentiated, in rabbit muscle extracts, the action of enolase from that of phosphoglyceromutase and pyruvic acid kinase (1). Since that time enolase has been crystallized from yeast by Warburg and Christian (2) and extensively investigated, but the enzyme bearing the same function in muscle tissue has received comparatively little study. A preparation of crystallin...

Kanetsuna, Fuminori (Instituto Venezolano de Investigaciones Cientificas, Caracas, Venezuela), and Luis M. Carbonell. Enzymes in glycolysis and the citric acid cycle in the yeast and mycelial forms of Paracoccidioides brasiliensis. J. Bacteriol. 92:1315-1320. 1966.-Enzymatic activities in glycolysis, the hexose monophosphate shunt, and the citric acid cycle in cell-free extracts of the yeast an...

The fermentation of ribose-5-phosphate by cell-free extracts of yeast is characterized by the equimolar formation of COZ, ethyl alcohol, and inorganic phosphate (1). Dickens (1) and Sable (2) suggested from their studies of pentose phosphate metabolism by cell-free yeast preparations that fermentation proceeded in the following manner: (1) cleavage of ribosed-phosphate to a 2-carbon fragment an...

The ubiquitin-dependent proteolysis of mitotic cyclin B, which is catalyzed by the anaphase-promoting complex/cyclosome (APC/C) and ubiquitin-conjugating enzyme H10 (UbcH10), begins around the time of the metaphase-anaphase transition and continues through G1 phase of the next cell cycle. We have used cell-free systems from mammalian somatic cells collected at different cell cycle stages (G0, G...

A multisubunit protein complex, termed cohesin, plays an essential role in sister chromatid cohesion in yeast and in Xenopus laevis cell-free extracts. We report here that two distinct cohesin complexes exist in Xenopus egg extracts. A 14S complex (x-cohesin(SA1)) contains XSMC1, XSMC3, XRAD21, and a newly identified subunit, XSA1. In a second 12.5S complex (x-cohesin(SA2)), XSMC1, XSMC3, and X...

Depletion of endoplasmic reticulum Ca2+ stores leads to the entry of extracellular Ca2+ into the cytoplasm, a process termed capacitative or store-operated Ca2+ entry. Partially purified extracts were prepared from the human Jurkat T lymphocyte cell line and yeast in which Ca2+ stores were depleted by chemical and genetic means, respectively. After microinjection into Xenopus laevis oocytes, th...

We have identified a human splicing factor required for the second step of pre-mRNA splicing. This new protein, hPrp18, is 30% identical to the yeast splicing factor Prp18. In HeLa cell extracts immunodepleted of hPrp18, the second step of pre-mRNA splicing is abolished. Splicing activity is restored by the addition of recombinant hPrp18, demonstrating that hPrp18 is required for the second ste...

The enzyme which catalyzes the phosphorylation of glucose and fructose was described in 1927 by Meyerhof (1). He found that muscle extracts which split polysaccharides and hexose phosphates to lactic acid but were unable to ferment hexoses could be enabled to ferment glucose and fructose by addition of a protein fraction from bakers’ yeast. The same protein fraction activated the aerobic oxidat...

mite allergens. Although mites were first grown on human skin scales collected from barber shops and on yeast [1] , other food media used included fish food flakes, dried Daphnia, dog food, rodent chow, several cereal preparations, and even mold cultures [2] . Due to their position in the trophic chain, mites mainly feed on proteins found in house and mattress dust. A supplement of yeast is als...

epididymal spermatozoa. The biological activity of the extracts seemed to result, at least in part, from their ability to prevent energy utilization by uncoupling oxidative phosphorylation (8, 11). More recently, it has been possible to separate the yeast fermentation stimulating activity from that which causes uncoupling of oxidative phosphory lation in rat kidney or liver preparations. In fre...