arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2510.03326q-bio.BMcs.AI
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NS-Pep:采用非标准氨基酸的从头肽设计

NS-Pep: De novo Peptide Design with Non-Standard Amino Acids

Center of Excellence for Smart Health(智能健康卓越中心);Syneron Technology(Syneron技术公司);King Abdullah University of Science and Technology (KAUST)(国王 Abdullah 科学与技术大学(KAUST))

Tao Guo, Junbo Yin, Yu Wang, Xin Gao

AI总结:

针对现有肽设计方法仅支持标准氨基酸、非标准氨基酸(NSAAs)数据长尾分布及侧链建模不足的问题,提出含RFGM、PSP、IAW模块的NS-Pep框架,可实现含NSAA的肽序列结构协同设计与折叠,性能显著优于现有方法。

摘要:

掺入非标准氨基酸(NSAAs)的肽类药物具备更高的结合亲和力与更优的药理学特性。然而,现有肽设计方法仅局限于标准氨基酸,支持NSAA的设计领域仍鲜有探索。我们提出NS-Pep,这是一个可协同设计含NSAA的肽序列与结构的统一框架。该研究的核心挑战在于NSAA的占比极低——即便是出现频率最高的SEP,在残基中的占比也不足0.4%,导致严重的长尾分布问题。为提升对稀有氨基酸的泛化能力,我们提出残基频率引导修正(RFGM)方法,通过频率感知的logit校准缓解过惩罚问题,该方法得到了理论与实证分析的双重支撑。此外,我们发现侧链建模不足会限制NSAA的几何表征能力。为此,我们引入渐进式侧链感知(PSP)模块实现从粗到细的扭转角与位置预测,同时提出交互感知加权(IAW)机制以突出口袋附近的残基。不仅如此,NS-Pep可自然泛化至含NSAA的肽折叠任务,弥补了现有工具的一大缺陷。实验结果表明,NS-Pep将序列恢复率与结合亲和力分别提升了6.23%和5.12%,且在肽折叠成功率上比AlphaFold3高出17.76%。

英文摘要:

Peptide drugs incorporating non-standard amino acids (NSAAs) offer improved binding affinity and improved pharmacological properties. However, existing peptide design methods are limited to standard amino acids, leaving NSAA-aware design largely unexplored. We introduce NS-Pep, a unified framework for co-designing peptide sequences and structures with NSAAs. The main challenge is that NSAAs are extremely underrepresented-even the most frequent one, SEP, accounts for less than 0.4% of residues-resulting in a severe long-tailed distribution. To improve generalization to rare amino acids, we propose Residue Frequency-Guided Modification (RFGM), which mitigates over-penalization through frequency-aware logit calibration, supported by both theoretical and empirical analysis. Furthermore, we identify that insufficient side-chain modeling limits geometric representation of NSAAs. To address this, we introduce Progressive Side-chain Perception (PSP) for coarse-to-fine torsion and location prediction, and Interaction-Aware Weighting (IAW) to emphasize pocket-proximal residues. Moreover, NS-Pep generalizes naturally to the peptide folding task with NSAAs, addressing a major limitation of current tools. Experiments show that NS-Pep improves sequence recovery rate and binding affinity by 6.23% and 5.12%, respectively, and outperforms AlphaFold3 by 17.76% in peptide folding success rate.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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