Agar Deeps

Agar deeps are prepared in the same manner as described for slants except that upon completion of sterilization, tubes are left vertical, rather than slanted, until agar has solidified. In this case, approximately 20 mL of agar is added to each screw-cap test tube prior to autoclaving. 

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When necessary, liquids may be made solid by the inclusion of agar at 1.5-2% (wt/vol). Agar is a complex polysaccharide prepared from seaweed. It is not utilized by bacteria/yeast and, at temperatures <45° C (113°F), maintains the medium in solid form. Solidified media may be prepared and poured after autoclaving as plates, as slants (slopes), or as agar deeps. Preparation of each is described as follows ... 

The photograph shows the two ml standard deep well plate with 1.6 ml TAP-agar. Transformant colonies where picked from plate, spread inside the wells with plating-beads and incubated for 12 days at 20°C under illumination. The plate was afterwards sealed with a MicroMat ... 

Pick up bacterial cells from the LB agar plate by wide side of teeth pick and rinse them into 1 ml of LBG medium in 96-deep-well plate covered with an AirPore Tape Sheet. 

After plating the bacterial colonies on agar plates, they are picked and placed individually in the deep wells of microtiter plates (96-format) containing LB medium with the aid of an appropriate robot. Up to 10 000 colonies can be handled per day. The LB medium is added with an 8-channel dispenser. 

Fig. 4.4 Phenotype of 4-hydroxybutyrate dehydrogenase-positive (A) and lipase/esterase-positive (B) E. coli clones. A, 4-Hydroxy-butyrate dehydrogenase-positive clones are marked by arrows. Tetrazolium indicator plates [37] containing 4-hydroxybutyrate as test substrate were employed for the screening procedure [9], Positive clones were identified by formation of a deep-red formazan inside the colonies. B, Lipase/esterase activity of the clones was detected on LB agar [32] containing tributyrin as test substrate [14]. Zones of clearance around the colonies were indicative for lipase/ esterase activity.

Fig. 8.2. Stages of enzyme screening. Microorganisms are grown in flasks or deep-well microplates. Separation of single clones is achieved either by FACS or by plating on agar plates and subsequent colony picking into microplates. Finally, assays are carried out in microplate formats using whole bacteria or cell extracts. Alternatively, bacterial clones can be directly screened on the level of colonies on indicator agar plates or during FACS.

In order to gain visual control during the electrophoretic migration, we have found the following technique satisfactory (W8). One indicator consists of a 35 % sol of dextran (mol. wt. 150,(XK)) colored a deep blue with bromophenol blue. A small drop is placed on the agar near the serum sample. Part of it will dye the serum albumin exclusively, since the serum globulins are only colored after denaturation. Thus, the albumin front will take on a pure bluish color and demonstrate anionic progress. 

Deeps test tubes filled with liquid agar and allowed to solidify while upright. 

Remove the uninoculated deep from rack. Remove cap and flame lip. Immediately inoculate by carefully inserting the wire into the center of the agar plug and pushing the wire to the bottom of the tube. 

Abstract— Hypothermic brain treatment for newborn babies are currently hindered by the lack of appropriate techniques for continuous and non-invasive measurement of deep brain temperature. Microwave radiometry (MWR) is one of the promising methods that is completely passive and inherently safe. Five-band microwave radiometer system and its feasibility were reported with a confidence interval level of the temperature estimation of about 1.6 °C at 5 cm depth from the surface. This result was not good enough for clinical application because clinical requirement is less than 1 °C for both accuracy and stability. This paper describes the improved result of temperature resolutions of the five radiometer receivers, and shows the new confidence interval obtained form temperature measurement experiment using an agar phantom based on a water-bath. Temperature resolutions were 0.103, 0.129, 0.138, 0.105 and 0.111 °C for 1.2, 1.65, 2.3, 3.0 and 3.6 GHz receiver, respectively, and new confidence interval was 0.51 °C at 5 cm from surface. We believe that the system takes a step closer to the clinical hypothermic treatment. 

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