Levin Y, Khare R K, Abel G, Hill D, Eriotou-Bargiota E, Becker J M, Naider F
Department of Chemistry, College of Staten Island, City University of New York 10301.
Biochemistry. 1993 Aug 17;32(32):8199-206. doi: 10.1021/bi00083a021.
Seven His2 analogs of the Saccharomyces cerevisiae [Nle12]alpha-factor, WXWLQLKPGQP(Nle)Y, where X = beta-D-thienylalanine, beta-L-thienylalanine, 1-D-methylhistidine, 1-L-methylhistidine, 3-D-methylhistidine, 3-L-methylhistidine, and beta-3-L-pyridylalanine, were synthesized and purified to homogeneity. Assays were carried out on binding to the alpha-factor receptor and of biological activity determined by either growth arrest or morphological changes in target cells. In the L-isomer, replacement of the imidazole of histidine by thiophene or 3-pyridyl groups or derivatization of either nitrogen of the imidazole ring by methylation resulted in a 2-100-fold decrease in bioactivity. D-Isomers of the beta-thienylalanyl-, 1-methylhistidinyl-, or 3-methylhistidinyl-alpha-factors did not possess measurable bioactivity with the exception of comparatively low activity of the 3-D-methylhistidinyl and 1-D-methylhistidinyl-alpha-factors in the morphogenesis assay. In contrast, both active and inactive analogs demonstrated binding affinities 10-20-fold less than that of [Nle12]alpha-factor. These results indicate that the histidine residue of alpha-factor is not required for binding to the receptor or for biological activity and that bioactivity and binding can be dissociated through the use of pheromone analogs.
合成并纯化了酿酒酵母[Nle12]α因子的7种His2类似物，即WXWLQLKPGQP(Nle)Y，其中X = β-D-噻吩丙氨酸、β-L-噻吩丙氨酸、1-D-甲基组氨酸、1-L-甲基组氨酸、3-D-甲基组氨酸、3-L-甲基组氨酸和β-3-L-吡啶基丙氨酸，使其达到均一性。对其与α因子受体的结合以及通过靶细胞生长停滞或形态变化测定的生物活性进行了检测。在L-异构体中，用噻吩或3-吡啶基取代组氨酸的咪唑，或通过甲基化对咪唑环的任一氮原子进行衍生化，导致生物活性降低2-100倍。β-噻吩丙氨酰基、1-甲基组氨酰基或3-甲基组氨酰基-α因子的D-异构体除了在形态发生测定中3-D-甲基组氨酰基和1-D-甲基组氨酰基-α因子具有相对较低的活性外，不具有可测量的生物活性。相比之下，活性和非活性类似物的结合亲和力均比[Nle12]α因子低10-20倍。这些结果表明，α因子的组氨酸残基对于与受体结合或生物活性不是必需的，并且通过使用信息素类似物可以使生物活性和结合解离。
