Tissue Culture Nursery Technology of Curcuma alismatifolia‘Kimono Rose’

[Objectives]The paper was to study the tissue culture nursery technology of Curcuma alismatifolia‘Kimono Rose’.[Methods]By sterilizing and inoculating explants derived from disparate regions of C.alismatifolia,we identified the most optimal explants and optimized the culture conditions for cluster buds induction and proliferation.This was achieved by incorporating MS medium with varying concentrations of 6-BA and NAA,thereby establishing a foundation for the large-scale production of C.alismatifolia tissue culture seedlings.[Results]The optimal explant for C.alismatifolia was identified as a lateral bud.The most effective cluster buds induction medium was determined to be MS+6-BA 5 mg/L+NAA 0.1 mg/L+sucrose 25 g/L+agar 6.5 g/L.The optimal cluster buds proliferation medium was found to be MS+6-BA 3 mg/L+NAA 0.1 mg/L+sucrose 25 g/L+agar 6.5 g/L.[Conclusions]The findings of this study can provide a foundation for the enhancement of the industrialized breeding system of tissue culture propagation of C.alismatifolia.

Research Progress in Genetics and Molecular Biology of Curcuma L.

There are few studies on the genetic evolution of Curcuma L.,and it is easy to have synonyms or homonyms.In order to make better development and utilization of Curcuma L.,by consulting the relevant literature,the molecular biology and genetics of Curcuma L.were summarized,and discussed in this paper,in order to lay a foundation for the study of phylogeny and genetic evolution of Curcuma L.

Beyond dueling: roles of the type VI secretion system in microbiome modulation, pathogenesis and stress resistance

Bacteria inhabit diverse and dynamic environments,where nutrients may be limited and toxic chemicals can be prevalent.To adapt to these stressful conditions,bacteria have evolved specialized protein secretion systems,such as the type VI secretion system(T6SS)to facilitate their survival.As a molecular syringe,the T6SS expels various effectors into neighboring bacterial cells,eukaryotic cells,or the extracellular environment.These effectors improve the competitive fitness and environmental adaption of bacterial cells.Although primarily recognized as antibacterial weapons,recent studies have demonstrated that T6SSs have functions beyond interspecies competition.Here,we summarize recent research on the role of T6SSs in microbiome modulation,pathogenesis,and stress resistance.

The role of the type VI secretion system in the stress resistance of plant-associated bacteria

The type VI secretion system(T6SS)is a powerful bacterial molecular weapon that can inject effector proteins into prokaryotic or eukaryotic cells,thereby participating in the competition between bacteria and improving bacterial environmental adaptability.Although most current studies of the T6SS have focused on animal bacteria,this system is also significant for the adaptation of plant-associated bacteria.This paper briefly introduces the structure and biological functions of the T6SS.We summarize the role of plant-associated bacterial T6SS in adaptability to host plants and the external environment,including resistance to biotic stresses such as host defenses and competition from other bacteria.We review the role of the T6SS in response to abiotic factors such as acid stress,oxidation stress,and osmotic stress.This review provides an important reference for exploring the functions of the T6SS in plantassociated bacteria.In addition,characterizing these anti-stress functions of the T6SS may provide new pathways toward eliminating plant pathogens and controlling agricultural losses.

铜绿假单胞菌cntRLMN操纵子介导锌离子摄取的功能鉴定

【目的】本研究以铜绿假单胞菌PAO1(Pseudomonas aeruginosa PAO1,菌种编号ATCC15692)为对象,研究cntRLMN在锌离子摄取中的功能。【方法】在ΔznuBC的基础上,以同源重组的方法构建了cntRLMN的各种突变菌株,通过质粒接合转移的方法构建其互补菌株及lacZ转录融合报告菌株,运用β-半乳糖苷酶酶活检测研究了Zur蛋白对cntRLMN的转录调控,凝胶阻滞实验(EMSA)检验Zur蛋白与cnt启动子及cnt启动子的突变片段的体外结合,并进一步通过生长曲线分析对cntRLMN中cntR、cntL、cntN等基因的锌离子摄取功能进行了分析和鉴定。最终,通过构建大蜡螟幼虫的侵染模型来研究cntRLMN对铜绿假单胞菌毒力发挥的影响。【结果】lacZ转录融合的酶活分析显示cntRLMN受Zur蛋白的负调控,其表达以Zur蛋白依赖的方式受锌离子饥饿的诱导;EMSA实验的结果显示cntRLMN的启动子可以与His-Zur结合形成DNA-蛋白质复合体,结合位点为GCGTTATAGTATATCAT;生长曲线和大蜡螟幼虫侵染实验的分析结果显示ZnuBC和CntRLMN的功能存在互补性,仅znuBC和cntRLMN双缺失突变时菌株在限锌培养条件下的生长和对大蜡螟幼虫的毒性才受到显著抑制,说明CntRLMN代表另一种独立的锌离子摄取系统。【结论】cntRLMN是受Zur直接负调控的另一种独立的铜绿假单胞菌锌离子摄取系统,对铜绿假单胞菌毒力的发挥起重要作用。