Abstract
A reliable method has been developed for the isolation of host-independent (H-I; i.e., “saprophytic”) strains of Bdellovibrio from host-dependent (H-D; i.e., “parasitic”) cultures. The technique involves growing streptomycin-resistant (Smr) H-D cultures on streptomycin-susceptible (Sm8) host cells. A lysate containing large numbers of the Smr H-D cells and some remaining Sm8 host cells is transferred to a selection medium which contains the antibiotic. The Sm8 host cells in the lysate are killed, and the Smr H-I strains develop in broth within 3 to 6 days. By use of this method, it has been possible to isolate H-I strains from 16 different H-D Bdellovibrio strains studied. The frequency of occurrence of host independence is in the range of one H-I colony per 106 to 107 plaque-forming units of H-D bdellovibrios. The H-I cultures are nonfermentative, do not reduce nitrate, are strongly proteolytic, are oxidase-positive, and do not utilize 14 different carbon compounds as sources of energy for growth. Most H-I cultures are catalase-positive upon initial isolation from H-D lysates, but some cultures lose this enzyme upon subsequent transfers through host-free media. Most H-I bdellovibrios are pleomorphic, consisting of vibrio- to spiral-shaped cells typically measuring 0.3 to 0.4 μm in width and 1 to 10 μm in length. All H-I bdellovibrios have a cytochrome a and c component (H-I A3.12 differs from the other strains in the location of the peaks of the cytochrome spectrum). All are sensitive to oxytetracycline and (except for strain H-I A3.12) to the vibriostatic pteridine 0/129; most bdellovibrios, except for H-I A3.12, are generally uniformly resistant or susceptible to a given antibiotic. Bdellovibrio and Vibrio spp. have common cytochrome difference spectra and susceptibilities to oxytetracycline and to the vibriostatic pteridine 0/129. All H-I bdellovibrios examined produce an exocellular protease which digests heat-killed host cells. Bdellovibrios possessing predatory and bacteriolytic properties could be reselected from H-I bdellovibrio cultures growing in the presence of living host cells. Attempts to select for bacteriolytic isolates from Vibrio and Spirillum spp. were unsuccessul.
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- Burger A., Drews G., Ladwig R. Wirtskreis und Infektionscyclus eines neu isolierten Bdellovibrio bacteriovorus-Stammes. Arch Mikrobiol. 1968 May 8;61(3):261–279. [PubMed] [Google Scholar]
- Canale-Parola E., Rosenthal S. L., Kupfer D. G. Morphological and physiological characteristics of Spirillum gracile sp. n. Antonie Van Leeuwenhoek. 1966;32(2):113–124. doi: 10.1007/BF02097451. [DOI] [PubMed] [Google Scholar]
- GLAUERT A. M., KERRIDGE D., HORNE R. W. THE FINE STRUCTURE AND MODE OF ATTACHMENT OF THE SHEATHED FLAGELLUM OF VIBRIO METCHNIKOVII. J Cell Biol. 1963 Aug;18:327–336. doi: 10.1083/jcb.18.2.327. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lépine P., Guélin A., Sisman J., Lamblin D. Etude au microscope électronique de la lyse de Salmonella par Bdellovibrio bacteriovorus. C R Acad Sci Hebd Seances Acad Sci D. 1967 Jun 19;264(25):2957–2960. [PubMed] [Google Scholar]
- SEBALD M., VERON M. TENEUR EN BASES DE L'ADN ET CLASSIFICATION DES VIBRIONS. Ann Inst Pasteur (Paris) 1963 Nov;105:897–910. [PubMed] [Google Scholar]
- SHEWAN J. M., HODGKISS W. A method for the rapid differentiation of certain nonpathogenic, asporogenous bacilli. Nature. 1954 Jan 30;173(4396):208–209. doi: 10.1038/173208b0. [DOI] [PubMed] [Google Scholar]
- STOLP H., STARR M. P. BDELLOVIBRIO BACTERIOVORUS GEN. ET SP. N., A PREDATORY, ECTOPARASITIC, AND BACTERIOLYTIC MICROORGANISM. Antonie Van Leeuwenhoek. 1963;29:217–248. doi: 10.1007/BF02046064. [DOI] [PubMed] [Google Scholar]
- Seidler R. J., Starr M. P. Factors affecting the intracellular parasitic growth of Bdellovibrio bacteriovorus developing within Escherichia coli. J Bacteriol. 1969 Feb;97(2):912–923. doi: 10.1128/jb.97.2.912-923.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Seidler R. J., Starr M. P., Mandel M. Deoxyribonucleic acid characterization of Bdellovibrios. J Bacteriol. 1969 Nov;100(2):786–790. doi: 10.1128/jb.100.2.786-790.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Seidler R. J., Starr M. P. Structure of the flagellum of Bdellovibrio bacteriovorus. J Bacteriol. 1968 May;95(5):1952–1955. doi: 10.1128/jb.95.5.1952-1955.1968. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Shilo M., Bruff B. Lysis of Gram-negative bacteria by host-independent ectoparasitic Bdellovibrio bacteriovorus isolates. J Gen Microbiol. 1965 Sep;40(3):317–328. doi: 10.1099/00221287-40-3-317. [DOI] [PubMed] [Google Scholar]
- Simpson F. J., Robinson J. Some energy-producing systems in Bdellovibrio bacteriovorus, strain 6-5-S. Can J Biochem. 1968 Aug;46(8):865–873. doi: 10.1139/o68-129. [DOI] [PubMed] [Google Scholar]
- Stanier R. Y., Palleroni N. J., Doudoroff M. The aerobic pseudomonads: a taxonomic study. J Gen Microbiol. 1966 May;43(2):159–271. doi: 10.1099/00221287-43-2-159. [DOI] [PubMed] [Google Scholar]
- Starr M. P., Baigent N. L. Parasitic interaction of Bdellovibrio bacteriovorus with other bacteria. J Bacteriol. 1966 May;91(5):2006–2017. doi: 10.1128/jb.91.5.2006-2017.1966. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Varon M., Shil M. Interacton of Bdellovibrio bacteriovorus and host bacteria. I. Kinetic studies of attachment and invasion of Escherichia coli B by Bdellovibrio bacteriovorus. J Bacteriol. 1968 Mar;95(3):744–753. doi: 10.1128/jb.95.3.744-753.1968. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Véron M. Taxonomie numériques de vibrions et de certaines bactéries comparables. II. Corrélation entre les similitudes phénétiques et la composition en bases de l'ADN. Ann Inst Pasteur (Paris) 1966 Dec;111(6):671–709. [PubMed] [Google Scholar]