Decreasing trend of the recoverbility of bacterial cultures on solid media in the course of preservation

Profiling the growth of bacterial cultures over time can be a tedious and error-prone process. Here, we present the development and evaluation of the use of the ODity platform to optically measure bacterial cell densities non-invasively. The digital growth data for E. coli MG1655 was calibrated against colony forming units (CFU/mL) obtained by plating on solid media. Diauxic-like shifts of liquid E. coli MG1655 cultures grown at 37°C in LB media were observed at densities as low as 2.9 × 107 ± 1.2 CFU/mL. The shift occurred at a significantly higher cell density (6.0 × 107 ± 1.2 CFU/mL) when the bacteria were cultured at 31°C. These shifts were only short lived, 15.2 ± 1.5 and 20.8 ± 1.8 min at 37°C and 31°C, respectively, with the previous growth rate restored thereafter. We measured minimum doubling times of 17.0 ± 1.1 and 24.8 ± 0.9 min at 37°C and 31°C, respectively. These results demonstrate that the growth and growth rate of bacterial cultures can be accurately determined non-invasively using the ODity device.

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The adaptation of bacterial cultures during the lag phase in media containing new substrates or antibacterial agents

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1957.0161 ◽

1957 ◽

Vol 242 (1228) ◽

pp. 143-143 ◽

Cited By ~ 1

Keyword(s):

Adaptive Response ◽

Liquid Culture ◽

Antibacterial Agents ◽

Carbon Sources ◽

Lag Phase ◽

Liquid Media ◽

Bacterial Cultures ◽

Solid Media ◽

Mutant Cells ◽

Selection Of

(This paper has been published in full in Proceedings B, 147, 247) Of a series of seventeen experiments in which cells of Bact. coli mutabile and Bact. coli ( K 12) were allowed to lag in media containing all the materials necessary for growth and division, but with lactose and D-arabinose or dulcitol respectively as sole carbon sources, there were eight experiments in which it was found, when samples were withdrawn at intervals during the lag phase and were plated on solid media containing the same carbon source, that the longer the cells had remained in the liquid medium the shorter was the plate lag. Since the majority of the cells in the liquid culture took part in this response it is interpreted as an adaptation involving the bulk of the population and does not represent the selection of a few mutant cells. In the other nine experiments the reduction in lag was also observed, but since the growth of the culture took place almost simultaneously with this reduction it was not possible to draw any definite conclusion from them. In another experiment involving the adaptation of Bact. coli mutabile to resist chloramphenicol, a definite adaptive response was again obtained. Similar experiments in liquid media lacking a nitrogen source or in phosphate buffer show that the adaptation of Bact. coli mutabile to lactose and to chloramphenicol and that of Bact. lactis aerogenes to D-arabinose in the presence of streptomycin can also go a considerable way in media which do not contain all the materials necessary for growth and division. Here again it is not necessary to postulate the presence of special mutant cells.

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THE VASELINE TUBE AND SYRINGE METHOD OF MICRO GAS ANALYSIS OF BACTERIAL CULTURES

Journal of Experimental Medicine ◽

10.1084/jem.35.5.667 ◽

1922 ◽

Vol 35 (5) ◽

pp. 667-684

Author(s):

J. Howard Brown

Keyword(s):

Closed System ◽

Gas Production ◽

Gas Analysis ◽

Small Samples ◽

Co2 Production ◽

Bacterial Cultures ◽

Solid Media ◽

Fluid Media ◽

Tuberculin Syringe ◽

Constant Quantity

There has been described the use of the vaseline tube and the tuberculin syringe for the study of gas production by bacteria. A comparison is made of some of the results obtained by the use of the method here described, the Smith fermentation tube, and the tube of Eldredge and Rogers. The reports of CO2 production by certain streptococci by Ayers, Rupp, and Mudge and by Bacterium typhosus by Nichols have been confirmed by the author's method. The data presented serve to illustrate the accuracy and technical possibilities of the method. In addition to economy of glassware, medium, and labor, the vaseline tube and syringe method of micro gas analysis possesses the following advantages. (1) Gas produced above either liquid or solid media may be measured and analyzed. (2) The gas produced may be measured in terms of a definite and constant quantity of medium used. (3) The vaseline tube provides a closed system from which gases do not escape into the air. (4) Separate determinations of the CO2 produced in and above fluid media may be made. (5) Determinations may be made from very small samples of material. (6) Numerous gas analyses of the same culture may be made at various times during the growth of the culture without contaminating or destroying it. (7) Gas production may be observed under both anaerobic and controlled aerobic conditions.

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Decreasing trend of the recoverbility of bacterial cultures on solid media in the course of preservation

Nippon Saikingaku Zasshi ◽

10.3412/jsb.15.650 ◽

1960 ◽

Vol 15 (7) ◽

pp. 650-654

Author(s):

Toyoho MUROHASHI ◽

Konosuke YOSHIDA

Keyword(s):

Bacterial Cultures ◽

Solid Media

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Ultrastructure and Morphology of the Neurospora Crassa Cell Wall Mutants, Slime And Slime X, Using Tem and Sem

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100090257 ◽

1976 ◽

Vol 34 ◽

pp. 54-55

Author(s):

Karen S. Howard ◽

H. D. Braymer ◽

M. D. Socolofsky ◽

S. A. Milligan

Keyword(s):

Cell Wall ◽

Neurospora Crassa ◽

Wild Type ◽

Morphological Comparison ◽

Small Areas ◽

Solid Media ◽

Thin Sectioning ◽

X Cells ◽

Mutant Cells ◽

Isolated Cell

The recently isolated cell wall mutant slime X of Neurospora crassa was prepared for ultrastructural and morphological comparison with the cell wall mutant slime. The purpose of this article is to discuss the methods of preparation for TEM and SEM observations, as well as to make a preliminary comparison of the two mutants.TEM: Cells of the slime mutant were prepared for thin sectioning by the method of Bigger, et al. Slime X cells were prepared in the same manner with the following two exceptions: the cells were embedded in 3% agar prior to fixation and the buffered solutions contained 5% sucrose throughout the procedure.SEM: Two methods were used to prepare mutant and wild type Neurospora for the SEM. First, single colonies of mutant cells and small areas of wild type hyphae were cut from solid media and fixed with OSO4 vapors similar to the procedure used by Harris, et al. with one alteration. The cell-containing agar blocks were dehydrated by immersion in 2,2-dimethoxypropane (DMP).

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TEM processing procedure for a bacillus organism grown on solid media

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100160674 ◽

1990 ◽

Vol 48 (3) ◽

pp. 624-625

Author(s):

Jane Payne ◽

Philip Coudron

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Fume Hood ◽

Vacuum Aspiration ◽

Solid Media ◽

Transmission Electron ◽

Solid Agar ◽

Processing Procedure ◽

Agar Media ◽

Rat Bone

This transmission electron microscopy (TEM) procedure was designed to examine a gram positive spore-forming bacillus in colony on various solid agar media with minimal artifact. Cellular morphology and organization of colonies embedded in Poly/Bed 812 resin (P/B) were studied. It is a modification of procedures used for undecalcified rat bone and Stomatococcus mucilaginosus.Cultures were fixed and processed at room temperature (RT) under a fume hood. Solutions were added with a Pasteur pipet and removed by gentle vacuum aspiration. Other equipment used is shown in Figure 3. Cultures were fixed for 17-18 h in 10-20 ml of RT 2% phosphate buffered glutaraldehyde (422 mosm/KgH2O) within 5 m after removal from the incubator. After 3 (30 m) changes in 0.15 M phosphate buffer (PB = 209-213 mosm/KgH2O, pH 7.39-7.41), colony cut-outs (CCO) were made with a scalpel.

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