In silico curation of QTL-rich clusters and candidate gene identification for plant height of bread wheat

Many genetic loci for wheat plant height(PH) have been reported, and 26 dwarfing genes have been catalogued. To identify major and stable genetic loci for PH, here we thoroughly summarized these functionally or genetic verified dwarfing loci from QTL linkage analysis and genome-wide association study published from 2003 to 2022. A total of 332 QTL, 270 GWAS loci and 83 genes for PH were integrated onto chromosomes according to their locations in the IWGSC RefSeq v2.1 and 65 QTL-rich clusters(QRC) were defined. Candidate genes in each QRC were predicted based on IWGSC Annotation v2.1 and the information on functional validation of homologous genes in other species. A total of 38 candidate genes were predicted for 65 QRC including three GA2ox genes in QRC-4B-IV, QRC-5A-VIII and QRC-6A-II(Rht24) as well as GA 20-oxidase 2(TaSD1-3A) in QRC-3A-IV. These outcomes lay concrete foundations for mapbased cloning of wheat dwarfing genes and application in breeding.

Metalloprotein-inspired supramolecular photodynamic nanodrugs by multicomponent coordination for deep penetration and enhanced biofilm eradication

Bacterial infections exacerbate the formation of bacterial biofilms,leading to resistance to traditional drugs,persistent infection,and even threatening patient’s life.Efficient antimicrobial materials against drug-resistant bacterial biofilms are highly desired.In this study,a photodynamic nanodrug with bacterial targeting was constructed by cooperative coordination of zinc ion with an antimicrobial peptide with hydrophobic tripeptides on the side chains and the photosensitizer chlorin e6.The supramolecular nanodrug with a uniform spherical structure possessed high photosensitizer loading capacity and enhanced photodynamic efficacy,which could deep penetrate and eradicate methicillin-resistant Staphylococcus aureus(MRSA)biofilms upon 655 nm laser irradiation.Furthermore,in vivo experiments verified the efficient elimination of MRSA biofilms on implanted catheters.This study provides a novel strategy to fabricate metalloprotein-inspired supramolecular photodynamic nanodrugs against drugresistant bacterial biofilms-associated infections in vivo.

谷氨酸棒杆菌基因编辑的研究进展

谷氨酸棒杆菌是生产氨基酸、有机酸等的重要菌株,广泛应用于食品、医药领域。利用基因编辑技术对谷氨酸棒杆菌进行基因功能研究,在提高目的产物产量、发现新的基因功能等方面有重要意义。近年来,基因编辑技术发展日新月异,从基于同源重组的传统基因编辑技术到以人工核酸酶介导的基因编辑均在谷氨酸棒杆菌中得到合理应用。其中,CRISPR技术以其快速、简便、编辑效率高等优点成为现阶段研究者用于改造谷氨酸棒杆菌的主要技术,但是更为简单、高效的编辑手段依旧需要进一步研究开发,以获得优良菌株应用于工业生产中。

疏水性氨基酸的羟基化研究进展

羟基化氨基酸在生物技术和分子生物学中具有独特价值,具有抗真菌、抗菌、抗病毒和抗癌的特性。通过比较化学合成与生物催化合成羟基氨基酸的异同,选择具有高对映结构选择性的生物催化合成方法成为羟基氨基酸合成的首选。生物催化实现疏水性氨基酸的羟基化和羟化酶紧密相关,而羟化酶又是单核非血红素Fe(Ⅱ)和α-酮戊二酸依赖型双加氧酶(Fe/αKGDs)的一种,Fe/αKGDs存在共性催化机制。因此,疏水性氨基酸在被催化的过程中,会利用关键中间体高价铁-超氧复合体(Fe(Ⅳ)=O)引起多种氧化转化,从而完成羟基化过程。文中就疏水性氨基酸的羟基化合成及功能应用,尤其是(2S,3R,4S)-4-羟基-异亮氨酸(4-HIL)和羟脯氨酸,进行了详细的阐述,探讨了Fe/αKGDs的共性催化反应机制,并对羟基氨基酸在基础研究和工业中的应用进行了综述。

活性氧引发二乙炔脂肽在活细胞内原位聚合

近年来,活细胞内原位聚合由于具有高细胞内化效率和延长药物滞留时间的特性而备受关注.然而,对原位聚合过程的可视化追踪仍缺失,聚合过程对细胞功能的影响机制尚不明确,极大地限制了其在生物医学领域的应用.在本文中,我们设计了一种带正电荷的Y型二乙炔脂肽(Y-DLPA1),系统研究了其在细胞内微环境中活性氧引发的原位聚合行为.作为对照组,具有类似分子拓扑结构的两性离子型二乙炔脂肽Y-DLPA2和负电荷型二乙炔脂肽Y-DLPA3在水溶液中能够发生紫外光辐照聚合,而在细胞内微环境中无法聚合.尤为重要的是,聚合后的Y-DLPA1具有红色荧光,实现了原位可视化追踪细胞内聚合过程.此外,二乙炔脂肽原位聚合反应能够诱导肿瘤细胞凋亡,增加细胞黏度,降低细胞运动能力,为抑制肿瘤转移提供了一种潜在的策略.