Palumbo J D, Phillips D A, Kado C I
Department of Plant Pathology, University of California, Davis, CA 95616, USA.
Arch Microbiol. 1998 May;169(5):381-6. doi: 10.1007/s002030050586.
Agrobacterium tumefaciens strain 1D1609 is reported here as the first field isolate from alfalfa (Medicago sativa L.). Unlike well-characterized A. tumefaciens strains such as C58 and Ach5, strain 1D1609 is highly virulent on alfalfa and has a distinctive host range. Interestingly, strain 1D1609 is naturally resistant to kanamycin and spectinomycin. The Ti plasmid in strain 1D1609 is an octopine-type; thus, tumors formed by strain 1D1609 synthesize octopine, which is utilized by the bacterium as a sole carbon source. Reciprocal exchange of Ti plasmids between strains 1D1609 and C58 showed that both chromosomal and Ti plasmid genes in strain 1D1609 contribute specifically to tumor formation on alfalfa. In addition, the nondormant CUF101 alfalfa cultivar from which strain 1D1609 was isolated was significantly more susceptible to all Agrobacterium strains tested than was the dormant Agate cultivar.
本文报道了根癌农杆菌菌株1D1609，它是从苜蓿（紫花苜蓿）中分离得到的首个田间菌株。与特征明确的根癌农杆菌菌株如C58和Ach5不同，1D1609菌株对苜蓿具有高致病性，且具有独特的宿主范围。有趣的是，1D1609菌株对卡那霉素和壮观霉素天然耐药。1D1609菌株中的Ti质粒是章鱼碱型；因此，由1D1609菌株形成的肿瘤合成章鱼碱，该细菌将其用作唯一碳源。1D1609菌株和C58菌株之间Ti质粒的相互交换表明，1D1609菌株中的染色体基因和Ti质粒基因都对苜蓿上的肿瘤形成有特异性贡献。此外，分离出1D1609菌株的非休眠苜蓿品种CUF101比休眠的玛瑙品种对所有测试的农杆菌菌株更敏感得多。
