Motorin Nikita A, Makarov Gennady I, Rekstina Valentina V, Evtushenko Evgeniy G, Sabirzyanov Fanis A, Ziganshin Rustam H, Shaytan Alexey K, Kalebina Tatyana S
Faculty of Biology, Lomonosov Moscow State University, Moscow 119991, Russia.
Laboratory of the Multiscale Modeling of Multicomponent Materials, South Ural State University, Chelyabinsk 454080, Russia.
Int J Mol Sci. 2024 Dec 22;25(24):13703. doi: 10.3390/ijms252413703.
Bgl2p is a major, conservative, constitutive glucanosyltransglycosylase of the yeast cell wall (CW) with amyloid amino acid sequences, strongly non-covalently anchored in CW, but is able to leave it. In the environment, Bgl2p can form fibrils and/or participate in biofilm formation. Despite a long study, the question of how Bgl2p is anchored in CW remains unclear. Earlier, it was demonstrated that Bgl2p lost the ability to attach in CW and to fibrillate after the deletion of nine amino acids in its C-terminal region (CTR). Here, we demonstrated that a Bgl2p anchoring is weakened by substitution Glu-233/Ala in the active center. Using AlphaFold and molecular modeling approach, we demonstrated the role of CTR on Bgl2p attachment and supposed the conformational possibilities determined by the presence or absence of an intramolecular disulfide bond, forming by Cys-310, leading to accessibility of amyloid sequence and β-turns localized in CTR of Bgl2p for protein interactions. We hypothesized the mode of Bgl2p attachment in CW. Using atomic force microscopy, we investigated fibrillar structures formed by peptide V187MANAFSYWQ196 and suggested that it can serve as a factor leading to the induction of amyloid formation during interaction of Bgl2p with other proteins and is of medical interest being located close to the surface of the molecule.
Bgl2p是酵母细胞壁（CW）中一种主要的、保守的组成型葡聚糖基转移酶，具有淀粉样氨基酸序列，通过强非共价键锚定在CW中，但能够离开它。在环境中，Bgl2p可以形成纤维和/或参与生物膜形成。尽管经过了长期研究，但Bgl2p如何锚定在CW中的问题仍不清楚。早些时候，已证明Bgl2p在其C端区域（CTR）缺失九个氨基酸后失去了在CW中附着和形成纤维的能力。在这里，我们证明了活性中心的Glu-233/Ala替换会削弱Bgl2p的锚定作用。使用AlphaFold和分子建模方法，我们证明了CTR对Bgl2p附着的作用，并推测了由分子内二硫键的存在与否所决定的构象可能性，该二硫键由Cys-310形成，导致Bgl2p的CTR中淀粉样序列和β转角可用于蛋白质相互作用。我们假设了Bgl2p在CW中的附着模式。使用原子力显微镜，我们研究了由肽V187MANAFSYWQ196形成的纤维状结构，并表明它可以作为一个因素，在Bgl2p与其他蛋白质相互作用期间导致淀粉样形成的诱导，并且由于其靠近分子表面而具有医学意义。
