A bacterium with the general properties of a member of the family Pseudomonadaceae has been isolated from infusions of decaying marine algae (Nova Scotia). The organism possesses rigid, randomly arranged appendages that are nonprosthecate and can best be described as "echinuliform" (spinelike).During a survey of bacterial populations in infusions of decaying marine algae (Fink Cove, Nova Scotia), 60 organisms were isolated in pure culture. One of these possessed, in addition t o a polar monotrichous flagellum, numerous straight spines (Fig. 1). After subculturing this organism for 3 months at 20 C on ZoBell medium (7), it was observed that both the proportion of cells with spines and the number of spines per cell had greatly decreased when compared with the original isolate. In contrast, many more cells were flagellated. Subculturing such cultures at 35 C resulted in the production of many spines by most cells, but these failed t o produce flagella (Fig. 2).The bacterium is gram-negative and in young cultures is a coccobacillus measuring 1 t o 1.5 pm with rounded, somewhat pointed ends. In older cultures, long rods, as well as enlarged forms, are common. The organism occurs singly or, especially when spines are present, in clumps. When motile, a monotrichous polar flagellum is present with a wavelength of approximately 1.8 pm. The location of spines is unrestricted, and they measure about 70 nm in diameter and 1 to 3 pm in length. Striations, present on the surface of the spines, are 12 nm apart. Usually, either spines or a flagellum are present, but both have rarely been observed on the same cell.Colonies grown on ZoBell seawater agar for 48 h at 20 C measure 2 mm in diameter and are umbonate, fimbriate, and unpigmented. Growth on slants is filiform with a slight erose edge.The bacterium is a facultative aerobe with an optimum growth temperature of 32 C. The organism will not grow in the absence of salt, and all media used for its cultivation are reconstituted in synthetic seawater containing 3% salt. Acid (as measured by pH change), but not gas, is produced from lactose, glucose, sucrose, galactose, mannose, and arabinose. Urea is hydrolyzed, catalase and oxidase are produced, but gelatin is not liquefied. Indole, methyl red, Voges-Proskauer, and nitrate reduction tests are all negative. Acetic acid is not produced from 5% ethanol. The guanine plus cytosine content of the bacterial deoxyribonucleic acid, as determined by buoyant density measurement, is 57.7%. These properties are typical of certain members of the family Pseudo m o nadaceae.To date only three reports of bacteria with spines as described herein have been made. Leifson ( 3 ) isolated an organism from the DuPage river near Chicago, but he was unable to maintain it in the spined form in pure culture. Staley (6) observed an organism with similar appearance in fresh water from the Putah Creek overflow (Davis, Calif.) and described it as possessing type 5 appendages, but he did not culture it. Moll and Ahrens (4) isolated a bacterium, thought t o be ...
A marine bacterium produces appendages (spines) which consist of rigid tubes, about 70 nm in diameter. These are expanded at the base and attached to, but not originating in, the cell wall. The wall of the spine is smooth on the inside but ridged on the outside. The ridges, which appear as striations in shadowed or negative-stained preparations, are continuous along the length of the spine and helically arranged. The fine structure of these spines is demonstrated.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.