The L-(+)-lactate dehydrogenase (L-lactate:NAD+ oxidoreductase, EC 1.1.1.27) of Streptococcus lactis C10, like that of other streptococci, was activated by fructose 1,6-diphosphate (FDP). The enzyme showed some activity in the absence of FDP, with a pH optimum of 8.2; FDP decreased the Km for both pyruvate and reduced nicotinamide adenine dinucleotide (NADH) and shifted the pH optimum to 6.9. E...

A new turbidimetric method for the direct measurement of the solubility of oxy- and deoxyhemoglobins (Hb) in concentrated phosphate buffer has been established. The principle of the method is the formation of a homogeneous emulsion when hemoglobin is introduced in concentrated phosphate buffer. The solubility of the oxy and deoxy forms of Hb A, Hb S, Hb C, Hb F, and Hb CHarlem (beta 6Glu leads ...

The pharmacokinetic models proposed for atracurium or cisatracurium are based on the assumption that spontaneous degradation via Hofmann elimination proceeds in vivo at the same rate as measured in vitro at pH 7.4 and 37 degrees C. As different degradation rates have been reported for all 10 stereoisomers of atracurium measured together, for each of its three isomeric groups, and for the single...

Hydroxyapatite column chromatography can be used to purify filamentous bacteriophage--the phage most commonly used for phage display. Virions that have been partially purified from culture supernatant by two cycles of precipitation in 2% polyethylene glycol are adsorbed onto the matrix at a density of at least 7.6 x 10(13) virions (about 3 mg) per milliliter of packed bed volume in phosphate-bu...

When living cells of Nitella are first exposed to (1) phosphate buffer mixture, or (2) phosphoric acid, or (3) hydrochloric acid, or (4) sodium chloride, or (5) sodium borate, and are then placed in a solution of brilliant cresyl blue made up with a borate buffer mixture at pH 7.85, the rate of penetration of the dye into the vacuole is decreased as compared with the rate in the case of cells t...

The present study utilized different methods for purification of alkaline protease by using ammonium sulphate and acetone. Ammonium sulphate was found the best purifying agent and gave 109.09 fold purification of protease with 49.7% yield at 60% saturation. Dialysis was performed by using phosphate and Tris-HCl buffer and phosphate buffer was optimized to good dialyzing agent at pH 8.0.

1. Urea cycle enzymes and ornithine ketoacid transaminase were extracted from rat liver using various buffer systems and different procedures for the mechanical disintegration of the cells. Of the buffers tested, phosphate and glutathipne gave optimal results, whereas significant differences were found when other extracting media were used: activities of ornithine ketoacid transaminase and orni...

METHODS A 2.8M phosphate buffer is prepared by dissolving 21.7 Gm. dibasic potassium phosphate (K2HPO4) and 16.9 Gm. monobasic potassium phosphate (KH2PO4) in distilled water free of CO2. The volume is adjusted to 100 ml. To 1.8 ml. of this buffer, 20 mg. of sodium hydrosulfite (Na2S2O4) and 0.2 ml. of buffered hemolysate (3) are added in a small test tube. After 15 minutes or longer the mixtur...

Dibucaine, used as a differential inhibitor with acetyl-, propionyl-, and butyr. ylthiocholine as substrate, clearly identified the “usual” and “atypical” serum cholinesterases. Succinylcholine was also used successfully as a differential inhibitor with butyrylthiocholine as substrate. Sodium fluoride, used as a differential inhibitor, gave conflicting results, depending on whether Tris or phos...