Shpakov A O, Derkach K V, Uspenskaia Z I
Zh Evol Biokhim Fiziol. 2011 Mar-Apr;47(2):128-35.
Natural amino acids and sugars in intracellular eukaryotes are known to regulate adenylyl cyclase (AC) and guanylyl cyclase (GC) systems that control the most important cell processes. The goal of the present work consisted in study of effects of natural amino acids and sugars and some of their derivatives on AC and GC activities of infusoria Tetrahymena pyriformis and Dileptus anser. Methionine, arginine, lysine, and tryptamine stimulated basic AC activity of T. pyriformis, whereas alanine, thyrosine, and cysteine decreased it. Methionine, glycine, alanine, thyrosine, arginine, and to the lesser degree tryptamine and histidine stimulated AC of D. anser. The GC activity of T. pyriformis are increased in the presence of tryptamine, tryptophane, histidine, arginine, and lysine, whereas glycine and aspartic acid, on the contrary, decreased it. Tryptamine, tryptophan, leucine, glutamic acid, serine, histidine, and alanine stimulated the GC activity of D. anser. Glucose, fructose, and sucrose stimulated the basal AC activity of both infusorians and GC of T. pyriformis, with glucose and sucrose increasing AC of T. pyriformis twice, while that of D. anser 4.5 times. Lactose stimulated AC and GC of T. pyriformis and was inefficient with respect to the D. anser cyclases, whereas mannose and galactose did not affect the enzyme activities in both infusorians. The study of the chemotactic response of infusorians to amino acids and sugars indicates that involved in realization of this response can be signaling pathways both dependent on and independent of cyclic nucleotides. Thus, it has been established for the first time that several amino acids and sugars affect functional activity of enzymes with cyclase activity of the infusorians T. pyriformis and D. anser. This confirms the hypothesis that at early stages of evolution the large spectrum of comparatively simple natural molecules has a hormone-like action.
已知细胞内真核生物中的天然氨基酸和糖类可调节腺苷酸环化酶（AC）和鸟苷酸环化酶（GC）系统，这些系统控制着最重要的细胞过程。本研究的目的是研究天然氨基酸、糖类及其某些衍生物对梨形四膜虫和鹅颈双滴虫AC和GC活性的影响。蛋氨酸、精氨酸、赖氨酸和色胺刺激了梨形四膜虫的基础AC活性，而丙氨酸、酪氨酸和半胱氨酸则降低了该活性。蛋氨酸、甘氨酸、丙氨酸、酪氨酸、精氨酸，以及程度较轻的色胺和组氨酸刺激了鹅颈双滴虫的AC。在色胺、色氨酸、组氨酸、精氨酸和赖氨酸存在的情况下，梨形四膜虫的GC活性增加，而甘氨酸和天冬氨酸则相反，降低了其GC活性。色胺、色氨酸、亮氨酸、谷氨酸、丝氨酸、组氨酸和丙氨酸刺激了鹅颈双滴虫的GC活性。葡萄糖、果糖和蔗糖刺激了两种纤毛虫的基础AC活性以及梨形四膜虫的GC活性，其中葡萄糖和蔗糖使梨形四膜虫的AC增加了两倍，而使鹅颈双滴虫的AC增加了4.5倍。乳糖刺激了梨形四膜虫的AC和GC，但对鹅颈双滴虫的环化酶无效，而甘露糖和半乳糖对两种纤毛虫的酶活性均无影响。对纤毛虫对氨基酸和糖类的趋化反应的研究表明，参与这一反应的可能是依赖和不依赖环核苷酸的信号通路。因此，首次确定了几种氨基酸和糖类会影响梨形四膜虫和鹅颈双滴虫具有环化酶活性的酶的功能活性。这证实了以下假设：在进化的早期阶段，大量相对简单的天然分子具有类似激素的作用。
