Bhattacharyya Soma, Chaudhuri Paramita, Basu Arghya, Sengupta Subhabrata, Ghosh Anil Kumar
Department of Biotechnology, Indian Institute of Chemical Biology, Kolkata, India.
Indian J Exp Biol. 2005 Apr;43(4):360-8.
Effect of a potent methylation inhibitor oxidized adenosine (Adox), and a universal methyl group donor S-adenosyl-L-methionine (AdoMet) on trehalose metabolism was studied in two haploids of S. cerevisiae of mating types MATalpha, met3 (6460 -8D) and MATa, leu2, ura3, his4 (8534 -10A). Trehalose level decreased in presence of Adox in both strains. Both neutral trehalase (NT) and trehalose-6-phosphate (tre-6-p) synthase activities increased in presence of Adox in -8D strain. Decrease in trehalose level in -8D thus could not be explained in the light of increased tre-6-p synthase activity; however, it could be correlated with increased NT activity. In strain -10A, NT activity was reduced in presence of Adox while tre-6-p synthase activity increased. Enzyme activity profiles in -10A thus do not explain the reduced trehalose level on Adox treatment. Effect of AdoMet was not very prominent in either strain, though in -8D a small increase in trehalose level was seen on treatment. Intracellular AdoMet level of untreated cells of -10A was seen to be almost six times higher than that of -8D. Further, AdoMet treatment caused increase in its level compared to untreated cells, suggesting AdoMet uptake. No effect of either compound was seen on acid trehalase (AT) activity in any strain. The results suggest that there was a possible effect of demethylation on trehalose metabolism (particularly in the synthetic direction) in both strains, though effect of methylation was not very prominent, the reason for which is not very clear.
在酿酒酵母的两种单倍体MATα、met3（6460 - 8D）和MATa、leu2、ura3、his4（8534 - 10A）中，研究了一种强效甲基化抑制剂氧化腺苷（Adox）和一种通用甲基供体S - 腺苷 - L - 甲硫氨酸（AdoMet）对海藻糖代谢的影响。在两种菌株中，Adox存在时海藻糖水平降低。在 - 8D菌株中，Adox存在时中性海藻糖酶（NT）和海藻糖 - 6 - 磷酸（tre - 6 - p）合酶活性均增加。因此，鉴于tre - 6 - p合酶活性增加，无法解释 - 8D中海藻糖水平的降低；然而，这可能与NT活性增加有关。在 - 10A菌株中，Adox存在时NT活性降低而tre - 6 - p合酶活性增加。因此， - 10A中的酶活性谱无法解释Adox处理后海藻糖水平的降低。AdoMet的作用在两种菌株中都不是很显著，尽管在 - 8D中处理后海藻糖水平有小幅增加。未处理的 - 10A细胞的细胞内AdoMet水平几乎是 - 8D的六倍。此外，与未处理细胞相比，AdoMet处理导致其水平升高，表明AdoMet被摄取。在任何菌株中，两种化合物对酸性海藻糖酶（AT）活性均无影响。结果表明，去甲基化可能对两种菌株的海藻糖代谢（特别是合成方向）有影响，尽管甲基化的影响不是很显著，其原因尚不清楚。
