Abstract：
OBJECTIVE: At present, the inhibition of staphyloxanthin biosynthesis has emerged as a prominent strategy in combating methicillin-resistant Staphylococcus aureus (MRSA) infection. Nonetheless, there remains a limited understanding regarding the bio-structural characteristics of staphyloxanthin biosynthetic enzymes, as well as the molecular mechanisms underlying the interaction between inhibitors and proteins. Furthermore, the functional scope of these inhibitors is relatively narrow.
METHODS: In this study, we address these limitations by harnessing the power of deep learning techniques to construct the 3D structure of diapophytoene desaturase (CrtN). We perform efficient virtual screening and unveil alnustone as a potent inhibitor of CrtN. Further investigations employing molecular modelling, site-directed mutagenesis and biolayer interferometry (BLI) confirmed that alnustone binds to the catalytic active site of CrtN. Transcriptomic analysis reveals that alnustone significantly down-regulates genes associated with staphyloxanthin, histidine and peptidoglycan biosynthesis.
RESULTS: Under the effects of alnustone, MRSA strains exhibit enhanced sensitivity to various antibiotics and the host immune system, accompanied by increased cell membrane permeability. In a mouse model of systemic MRSA infection, the combination of alnustone and antibiotics exhibited a significant therapeutic effect, leading to reduced bacterial colony counts and attenuated pathological damage.
CONCLUSIONS: Alnustone, as a natural inhibitor targeting CrtN, exhibits outstanding antibacterial properties that are single-targeted yet multifunctional. This finding provides a novel strategy and theoretical basis for the development of drugs targeting staphyloxanthin producing bacteria.
METHODS: In this study, we address these limitations by harnessing the power of deep learning techniques to construct the 3D structure of diapophytoene desaturase (CrtN). We perform efficient virtual screening and unveil alnustone as a potent inhibitor of CrtN. Further investigations employing molecular modelling, site-directed mutagenesis and biolayer interferometry (BLI) confirmed that alnustone binds to the catalytic active site of CrtN. Transcriptomic analysis reveals that alnustone significantly down-regulates genes associated with staphyloxanthin, histidine and peptidoglycan biosynthesis.
RESULTS: Under the effects of alnustone, MRSA strains exhibit enhanced sensitivity to various antibiotics and the host immune system, accompanied by increased cell membrane permeability. In a mouse model of systemic MRSA infection, the combination of alnustone and antibiotics exhibited a significant therapeutic effect, leading to reduced bacterial colony counts and attenuated pathological damage.
CONCLUSIONS: Alnustone, as a natural inhibitor targeting CrtN, exhibits outstanding antibacterial properties that are single-targeted yet multifunctional. This finding provides a novel strategy and theoretical basis for the development of drugs targeting staphyloxanthin producing bacteria.
摘要：
目标：目前，在对抗耐甲氧西林金黄色葡萄球菌(MRSA)感染方面,抑制葡萄黄质生物合成已成为一项突出的策略.尽管如此，关于葡萄黄质生物合成酶的生物结构特征的理解仍然有限，以及抑制剂和蛋白质之间相互作用的分子机制。此外，这些抑制剂的功能范围相对较窄。
方法：在本研究中，我们通过利用深度学习技术的力量来构建双叶植物烯去饱和酶（CrtN）的3D结构来解决这些限制。我们进行了有效的虚拟筛选，并揭示了Alnustone作为CrtN的有效抑制剂。采用分子建模的进一步研究，定点诱变和生物层干涉法（BLI）证实了Alnustone与CrtN的催化活性位点结合。转录组学分析显示，alnustone显著下调与葡萄黄质相关的基因，组氨酸和肽聚糖生物合成。
结果：在Alnustone的作用下，MRSA菌株对各种抗生素和宿主免疫系统的敏感性增强，伴随着细胞膜通透性的增加。在全身性MRSA感染的小鼠模型中，alnustone和抗生素的组合显示出显著的治疗效果，导致细菌菌落数量减少和病理损伤减弱。
结论：Alnustone，作为靶向CrtN的天然抑制剂，表现出突出的抗菌性能，是单一的目标，但多功能。这一发现为开发针对葡萄黄质产生菌的药物提供了新的策略和理论基础。
方法：在本研究中，我们通过利用深度学习技术的力量来构建双叶植物烯去饱和酶（CrtN）的3D结构来解决这些限制。我们进行了有效的虚拟筛选，并揭示了Alnustone作为CrtN的有效抑制剂。采用分子建模的进一步研究，定点诱变和生物层干涉法（BLI）证实了Alnustone与CrtN的催化活性位点结合。转录组学分析显示，alnustone显著下调与葡萄黄质相关的基因，组氨酸和肽聚糖生物合成。
结果：在Alnustone的作用下，MRSA菌株对各种抗生素和宿主免疫系统的敏感性增强，伴随着细胞膜通透性的增加。在全身性MRSA感染的小鼠模型中，alnustone和抗生素的组合显示出显著的治疗效果，导致细菌菌落数量减少和病理损伤减弱。
结论：Alnustone，作为靶向CrtN的天然抑制剂，表现出突出的抗菌性能，是单一的目标，但多功能。这一发现为开发针对葡萄黄质产生菌的药物提供了新的策略和理论基础。
