Phosphorylation Saccharomyces cerevisiae

Gartner, A., Nasmyth, K., and Ammerer, G. (1992). Signal transduction in Saccharomyces cerevisiae requires tyrosine and threonine phosphorylation of FUS3 and KSS1. Genes Dev. 6 1280-1292. 

Figure 2. Histone H2A variants from yeast Saccharomyces cerevisiae S.c.), fruit fly Drosophila melanogaster D.m ), and human Homo sapiens H.s.). Two conserved domains distinguish H2A.Z-relatives (boxed regions amino acid sequences in the top). H2A.X possesses a conserved C-terminal stretch of four amino acids. The serine (red) becomes phosphorylated at sites of DNA damage. H2A ( Barr body-deficient ) and marcoH2A are present in mammals...

Figure 2. Current view of post-translational histone phosphorylation. Red flag mammahan specific or common, Blue flag Drosophila melanogaster specific, Black flag Saccharomyces cerevisiae specific. (See Colour Plate 18.)...

In Saccharomyces cerevisiae, multiple histone H2A phosphorylation sites have been characterized (Serine 122, Serine 129, Threonine 126) (Wyatt et al, 2003 Harvey et al, 2005 Redon et al, 2006). Histone H2A (S129) is essential for DNA double-strand-break responses (see Section 4) and histone H2A (SI22) is important for survival in the presence of DNA damage (Harvey et al, 2005) (Fig. 2). 

Wei Y, Yu L, Bowen J, Gorovsky MA, Allis CD (1999) Phosphorylation of histone H3 is required for proper chromosome condensation and segregation. Cell 97(1) 99—109 Wyatt HR, Liaw H, Green GR, Lustig AJ (2003) Multiple roles for Saccharomyces cerevisiae histone H2A in telomere position effect, Spt phenotypes and double-strand-break repair. Genetics 164(l) 47-64... 

Histone kinases responsible for N-phosphorylation have been isolated from regenerating rat liver [109] and Walker-256 carcinosarcoma cells [110]. One kinase with a pH optimum of 9.5 phosphorylated His-18 and His-75 of H4, while the other with a pH optimum of 6.5 phosphorylated lysine of HI. The enzyme from regenerating rat liver phosphorylated H4 at 1-phosphoryl histidine, while the carcinosarcoma enzyme phosphorylated H4 His at the position 3 [111]. Both kinases were cAMP independent [110]. Matthews and colleagues purified a 32-kDa histidine H4 kinase from yeast, Saccharomyces cerevisiae [112,113]. The enzyme phosphorylated His-75 (1-phosphoryl histidine) in H4. His-18 of H4 and other histidines in other core histones were not phosphorylated by this kinase [112]. Protein phosphatases 1, 2A, and 2C could dephosphorylate His-75 of H4 [114]. Applying a gel kinase approach to detect mammalian H4 histidine kinases, Besant and Attwood detected four activities in the 34-41 kDa range with extracts from porcine thymus [115]. 

Since the enzymatic activity of Ela was independent from increased phosphorylation the function of El phosphorylation remains unclear. From the three El homologs in the yeast Saccharomyces cerevisiae only Uba2p harbors a putative NLS. Uba2p is largely localized to the nucleus (Dohmen et al. 1995) and was shown to be essential for Smt3p-activation (Johnson et al. 

Transketolase from common yeast (Saccharomyces cerevisiae) is commercially available, but it is possible to work with a partially purified enzyme, isolated with little expense from spinach leaves.54 Transketolase catalyzes the transfer of a hydroxyacetyl group, reversibly from a ketose phosphate, or irreversibly from hydroxypyruvate to an acceptor aldose, phosphorylated or not.55 It requires thiamine pyrophosphate as a coenzyme, but only in catalytic amounts. In all the cases listed in Table V, the new chiral center, C-3 of the ketose, has the l-glycero configuration. 

Rotte C, Henze K, Muller M, Martin W (2000) Origins of hydrogenosomes and mitochondria -commentary. Curr Opin Microbiol 3 481-486 Saraste M (1999) Oxidative phosphorylation at the fin de siecle. Science 283 1488-1493 Sickmann A, Reinders J, Wagner Y, Joppich C, Zahedi R, Meyer HE, Schonfisch B, Perschil I, Chacinska A, Guiard B, Rehling P, Pfanner N, Meisinger C (2003) The proteome of Saccharomyces cerevisiae mitochondria. Proc Natl Acad Sci USA 100 13207-13212 Smith TF, Waterman MS (1981) Identification of common molecular subsequences. J Mol Biol 147 195-197... 

There was some evidence for the possible involvement of PolyPs localized in the cell periphery in the uptake and phosphorylation of sugars as energy and phosphate donors (Van Steveninck and Booij, 1964 Hofeler et al, 1987). Later, studies of the mechanisms of transport-associated phosphorylation of 2-deoxy-D-glucose in the yeast Kluyveromyces marxianus (Schuddemat et al, 1989b) and Saccharomyces cerevisiae (Schuddemat et al, 1990) resulted in the conclusion that PolyPs seem to replenish the Pj pool and therefore had an indirect role in sugar transport. 

Holmes, A.R., Monk, B.C., Cannon, R.D., and Uehara, Y. (2002) Candida glabrata ATP-binding cassette transporters Cdrlp and Pdhlp expressed in a Saccharomyces cerevisiae strain deficient in membrane transporters show phosphorylation-dependent pumping properties. 

Vitamin Bi is an essential co-factor for several enzymes of carbohydrate metabolism such as transketolase, pyruvate dehydrogenase (PDH), pyruvate decarboxylase and a-ketoglutarate dehydrogenase. To become the active co-factor thiamin pyrophosphate (TPP), thiamin has to be salvaged by thiamin pyrophosphokinase or synthesized de novo. In Escherichia coli and Saccharomyces cerevisiae thiamin biosynthesis proceeds via two branches that have to be combined. In the pyrimidine branch, 4-amino-5-hydroxymethy-2-methylpyrimidine (PIMP) is phosphorylated to 4-amino-2-methyl-5-hydroxymethyl pyrimidine diphosphate (PIMP-PP) by the enzyme HMP/HMP-P kinase (ThiD) however, the step can also be catalyzed by pyridoxine kinase (PdxK), an enzyme also responsible for the activation of vitamin B6 (see below). The second precursor of thiamin biosynthesis, 5-(2-hydroxyethyl)-4-methylthiazole (THZ), is activated by THZ kinase (ThiM) to 4-methyl-5-(2-phosphoethyl)-thiazole (THZ-P), and then the thia-zole and pyrimidine moieties, HMP-PP and THZ-P, are combined to form thiamin phosphate (ThiP) by thiamin phosphate synthase (ThiE). The final step, pyrophosphorylation, yields TPP and is carried out by thiamin pyrophosphorylase (TPK). 

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