该课题组人员在人类相关的拟杆菌种类中鉴定了1100种不同的DGRs，并发现了一个子集，使V型菌毛的粘附成分和相关蛋白多样化。课题组研究人员发现拟杆菌DGRs在物种间水平转移，表现出从高到低的活性水平，并优先改变粘附细胞器上配体结合残基的功能特征。当拟杆菌菌株与其他共生菌竞争时，特定的可变蛋白序列被富集。对来自不同门的母婴对2700个DGRs的分析表明，拟杆菌类DGRs不成比例地转移到阴道分娩的婴儿身上，在那里它们积极多样化。他们的观察结果为理解靶向基因组可塑性在塑造宿主相关微生物群落中的潜在作用提供了基础。
据介绍，产生多样性的逆转录因子（DGRs）通过使可变蛋白迅速多样化来加速进化。人类胃肠道微生物群是自然界中已知密度最大的DGRs，这表明它们在这种环境中起着适应性作用。
附：英文原文
Title: Targeted protein evolution in the gut microbiome by diversity-generating retroelements
Author: Benjamin R. Macadangdang, Yanling Wang, Cora L. Woodward, Jessica I. Revilla, Bennett M. Shaw, Kayvan Sasaninia, Gillian E. Varnum, Sara K. Makanani, Chiara Berruto, Umesh Ahuja, Jeff F. Miller
Issue&Volume: 2025-10-09
Abstract: Diversity-generating retroelements (DGRs) accelerate evolution by rapidly diversifying variable proteins. The human gastrointestinal microbiota harbors the greatest density of DGRs known in nature, suggesting that they play adaptive roles in this environment. We identified >1100 distinct DGRs among human-associated Bacteroides species and discovered a subset that diversify adhesive components of type V pili and related proteins. We show that Bacteroides DGRs are horizontally transferred across species, display activity levels ranging from high to low, and preferentially alter the functional characteristics of ligand-binding residues on adhesive organelles. Specific variable protein sequences are enriched when Bacteroides strains compete with other commensal bacteria in gnotobiotic mice. Analysis of >2700 DGRs from diverse phyla in mother-infant pairs shows that Bacteroides DGRs are disproportionately transferred to vaginally delivered infants where they actively diversify. Our observations provide a foundation for understanding the potential roles of targeted genome plasticity in shaping host-associated microbial communities.
DOI: adv2111
Source: https://www.science.org/doi/10.1126/science.adv2111