Agar plates minimal

Figure 3 Root fingerprints of Pseudomimets sp. associated with barley seedlings showing the production of siderophore by actively growing bacteria located in the zone of elongation behind the root tips. Root.s were pressed on to an iron-deficient minimal medium selective for Pseudomonas. After growth of the colonies, the production of siderophore was visualized by exposure of the agar plate to ultraviolet light, which causes the siderophore to Huoresce.

Salmonella Mutagenicity Test (Ames Test). The methods of bacterial culture, the verification of genetic markers, and the plate incorporation assay were essentially the same as described previously (14, 15). Petri dishes (90 mm) containing about 20 mL of 1.2 Noble agar in minimal Vogel Bonner Medium E supplied with excess biotine and... 

All host strains are stored on minimal agar plates (+ glucose) at 4°C and occasionally restreaked. 

Concentrated (X10) Eco RI buffer YT-medium 2 YT-medium Minimal agar plates... 

Streak cells out on a minimal agar plate and incubate at 37°C until discrete colonies are visible. Pick a single colony for a 2-5 ml overnight culture in YT medium. 

After incubation, the cells are plated with 9 ml of soft top agar onto minimal selection plates (the agar and plates both containing 1 M sorbitol, 8% glucose, and amino acid supplement lacking leucine). 

The level of GAS colonization during infection is monitored by enumeration of CPUs from two of live throat swabs taken at various intervals from each of the infected animals during the infection protocol. Throat swabs are processed to release adherent bacteria and plated on select agar to minimize growth of resident microbial flora from the macaque posterior pharynx. The three remaining throat swabs are snap frozen and stored at -80 °C. Our laboratory freezes these three throat swabs for future use in expression microarray and/or quantitative PCR analyses to monitor GAS and/or host gene expression during upper respiratory tract infection (21,22). 

Plates (15 by 100 mm plastic petri dishes) contained a base layer of 20 ml minimal agar (8) with 0.5% glucose. A standard pour-plate technique was used 0.1 ml of the proper dilution and 2 ml of molten 0.6% agar were added to a sterile tube, mixed, and poured over the surface of a base plate. The histidine overlay contained 0.1 ml of 0.1 M L-histidine per 40 ml of agar. Plates were incubated at 37°C for 48 hr, and the ratio of mutants total cells (mutant frequency or MF) was determined. 

Transfer 5 mg (several crystals) of each carbon compound to its appropriate site. We have found that placing these spots I-I.5 cm from edge of the plate minimizes spreading. If the same spatula is used for transfer, thoroughly clean between each compound. Once the first compound has been placed on agar substrate, maintain the plate upright. 

Minimal medium agar plates (see Chapter 4, maintenance of bacterial stocks)... 

Transformants, resistant to hygromycin B, were selected on minimal medium agar plates which were incubated at 30-37 C for 16-20 h and subsequently overlaid with agar containing 100 jjg/ml (A. niger) or 1000 jjg/ml (A, nidulans) of hygromycin B. Transformants appeared after 2-3 days of further incubation at a frequency of 5-15/jjg DNA (Table 2). 

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