摘要
【目的】Streptomyces sp.N2是本课题组分离筛选到的一株可产新型抗真菌活性物质(3-甲基-3,5-氨基-4-烯-吡喃-2-酮,分子式为C6H7O2N,农抗N2)的新种,此活性物质对桔青霉具有良好的拮抗效果。从生长特征、细胞形态学等角度,为揭示农抗N2在桔青霉生长发育中的抑菌作用机理奠定基础。【方法】首先采用常量培养基稀释法测定了农抗N2对桔青霉的最低抑菌浓度、杯碟法测定了不同浓度农抗N2对桔青霉的抑菌活性菌丝和生长量法测定了不同浓度农抗N2对桔青霉生长曲线的影响,并通过扫描电镜及透射电镜探究了农抗N2对桔青霉超微结构的影响。【结果】Streptomyces sp.N2所产农抗N2对桔青霉有较强的抑制作用,而且其机理初步判定为破坏桔青霉菌丝的菌丝结构,推迟了桔青霉对数期的到来而抑制菌体的生长。菌体最低抑菌浓度(3 d)为5.77μg/mL,其对应的抑菌圈大小为(13.04±1.06)mm。药液处理后,桔青霉生长对数期推迟了2 d。由扫描电镜以及透射电镜结果可推测,农抗N2可干扰桔青霉细胞壁合成,破坏细胞膜结构,致使细胞发生质壁分离。【结论】农抗N2对桔青霉的菌丝生长具有很强的抑制作用,且具有浓度效应,其对桔青霉的形态和结构有很大的破坏作用,可以推测农抗N2能够影响桔青霉细胞壁相关蛋白的合成,使细胞壁的通透性增强,影响其细胞膜及内部细胞器。
[Objective]Streptomyces sp.N2 is a new strain isolated by the research group that can produce new antifungal active substances(3-methyl-3,5-amino-4-ene-pyran-2-one.Its molecular formula is C6H7O2N,antifungalmycin N2).This active substance has a good antagonistic effect on Penicillium citrinum.The present study aimed to investigate the antagonistic mechanism of antifungalmycin N2 against Penicillium citrinum and its antibacterial activity evaluation.[Method]Firstly constant medium dilution method was used to measure the lowest inhibitory concentration of antifungalmycin N2 against Penicillium citrinum the antimicrobial activity of Penicillium citrinum with different concentrations of agricultural resistance antifungalmycin N2 was measured by oxford-cup tests and the hyphal growth method was used to determine the effects of different concentrations of antifungalmycin N2 on the growth curve of Penicillium citrinum,and the influence of antifungalmycin N2 on the ultrastructure of Penicillium citrinum was investigated by scanning electron microscope and transmission electron microscope.[Result]The results showed that antifungalmycin N2 had some inhibitory effect on P.citri⁃num.The mechanism was to destroy the hypha structure of P.citrinum mycelium and delay the arrival of logarithmic phase of P.citrinum,which inhibited the growth of bacteria.The minimum inhibitory concentration of bacteria(3 days)was 5.77μg/mL,and the corresponding size of inhibition zone diameter was 13.04±1.06 mm.The logarithmic growth period of P.citrinum was delayed by 2 days.It can be inferred from the results of scanning electron microscopy and transmission electron microscope that antifungalmycin N2 can interfere with the cell wall synthesis ofP.citrinum,destroy the cell membrane structure and cause the cell to separate plasma wall.[Conclusion]Antifungalmycin N2 has a strong inhibitory effect on the mycelial growth of Penicillium citrinum and has a concentration effect.It has a great effect on the morphology and structure of Penicillium citr
作者
刘群
王丽华
陈东海
彭伟建
徐家兴
李昆太
LIU Qun;WANG Li-hua;CHEN Dong-hai;PENG Wei-jian;XU Jia-xing;LI Kun-tai(Institute of Applied Microbiology,Jiangxi Agricultural University,Nangchang 330045,China;Jiangxi Medical Device Testing Center,Nanchang 330029,China)
出处
《江西农业大学学报》
CAS
CSCD
北大核心
2020年第3期487-493,共7页
Acta Agriculturae Universitatis Jiangxiensis
基金
国家自然科学基金项目(31760546)
江西省(青年)自然科学基金重大项目(20143ACB2100)
江西省青年科学家培养计划项目(20142BCB23025)。
