Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky pr. 33, 119071 Moscow, Russia.
Biochemistry (Mosc). 2012 May;77(5):502-10. doi: 10.1134/S0006297912050100.
Until recently food proteins were considered to be an energy source and a source of essential and nonessential amino acids required for protein synthesis and precursors of many vital biomolecules. However, we assumed earlier that food protein fragments might perform some regulatory functions. The theoretical justification for this assumption is advanced in this work. In the present work, the primary structures of protein fragments were compared with amino acid sequences of known natural regulatory oligopeptides in silico. It is shown that fragments formed as a result of animal food protein cleavage by proteolytic enzymes can exist in the gastrointestinal tract for a long time. Many of them are enzyme inhibitors, regulators of nervous, endocrine, and immune system, and possess antimicrobial and other activities. It has also been shown that the lifetime of fragments before their cleavage in the gastrointestinal tract could be enough for performing corrective functions. Thus, as a result of food protein fragmentation a dynamic pool of exogenous regulatory oligopeptides with functions changing as shorter fragments are generated may form. The detection of an endogenous-exogenous pool of regulatory molecules expands the significance and content of the Ashmarin-Obukhova hypothesis on a functional continuum of natural oligopeptides. The possible practical importance of these results is noted.
直到最近，食物蛋白质才被认为是一种能量来源，也是合成蛋白质所必需和非必需氨基酸的来源，同时也是许多重要生物分子的前体。然而，我们之前假设食物蛋白质片段可能具有一些调节功能。本工作为这一假设提供了理论依据。在本工作中，通过计算机对蛋白质片段的一级结构与已知天然调节性寡肽的氨基酸序列进行了比较。结果表明，由蛋白水解酶切割动物食物蛋白形成的片段可以在胃肠道中长时间存在。其中许多片段具有酶抑制剂、神经、内分泌和免疫系统调节剂的功能，还具有抗菌和其他活性。此外，还表明这些片段在胃肠道中被切割之前的寿命可能足以发挥纠正功能。因此，食物蛋白片段化可能会形成一个具有动态的外源性调节性寡肽库，其功能随着较短片段的生成而变化。内源性-外源性调节分子库的检测扩展了 Ashmarin-Obukhova 假说中关于天然寡肽功能连续体的意义和内容。这些结果可能具有实际意义。
