L-lactate

L(+)-lactate dehydro-genase lactate pymvate IFMN Iheme yt b[) respiratory chain... 

L-lactate dehydrogenase semm differentiation of heart cell damage... 

L-lactate-cytochrome c-oxidoreductase (flavocytochrome was isolated for the first time from the thermo-tolerant yeast H. polymorpha. The mentioned above enzyme preparations were used for construction of the biorecognition elements of electrochemical sensors. 

On the base of alcohol oxidase and flavocytochrome b, the enzymatic kits for selective assay of ethanol, methanol, formaldehyde and L-lactate were developed. 

L-Lactate. See Poly(L-lactate) (PLLA) Lactone polymerization, 84 Lacty, 28... 

L-Lactate dehydrogenase is a tetrameric enzyme whose four subunits occur in two isoforms, designated H (for... 

White blood cell count greater than 50 x 103/pL (50 x 109/L) Lactate dehydrogenase (LDH) levels greater than 1500 IU/L (1500 U/L or 25 uKat/L)... 

Ichihara, H., Fukushima, T., Imai, K. (1999).. Enantiomeric determination of d- and L-lactate in rat serum using high-performance liquid chromatography with a cellulose-type chiral stationary phase and fluorescence detection. Anal. Biochem. 269, 379-385. 

The bioluminescent determinations of ethanol, sorbitol, L-lactate and oxaloacetate have been performed with coupled enzymatic systems involving the specific suitable enzymes (Figure 5). The ethanol, sorbitol and lactate assays involved the enzymatic oxidation of these substrates with the concomitant reduction of NAD+ in NADH, which is in turn reoxidized by the bioluminescence bacterial system. Thus, the assay of these compounds could be performed in a one-step procedure, in the presence of NAD+ in excess. Conversely, the oxaloacetate measurement involved the simultaneous consumption of NADH by malate dehydrogenase and bacterial oxidoreductase and was therefore conducted in two steps. 

Michel P.E., Gautier S.M., Blum L.J., Effect of compartmentalization of the sensing layer on the sensitivity of a multienzyme-based bioluminescent sensor for L-lactate, Anal. Lett. 1996 29 (7) 1139-1155. 

Hikima S., Kakizaki T., Hasebel K., Enzyme sensor for L-lactate using differential pulse amperometric detection, Fresen. J. Anal. Chem. 1995 351(2-3) 237-240. 

Reliable measurements of L-lactate are of great interest in clinical chemistry, the dairy and vine industry, biotechnology, or sport medicine. In particular, blood lactate levels are indicative of various pathological states, including shock, respiratory insufficiencies, and heart and liver diseases. Silica sol-gel encapsulation of the lactate dehydrogenase and its cofactor was employed as a disposable sensor for L-lactate51. The sensor utilized the changes in absorbance or fluorescence from reduced cofactor nicotinamide adenine dinucleotide (NADH) upon exposure to L-lactate. 

Donovan, J.A., and Jennings, M.L. (1986) N-Hydroxysulfosuccinimido active esters and the L-( + )-lactate transport protein in rabbit erythrocytes. Biochemistry 25, 1538-1545. 

Other analytes recently determined by means of immobilized biolumines-cent enzymes are europium(III) [232], d- and L-lactate in beer [233], and d-sorbitol [234], A novel approach of the sensing layer design was reported for... 

Tildon, J. T.,McKenna,M. C.,Stevenson,J.H. etal.Transport of L-lactate by cultured rat brain astrocytes. Neurochem. Res. 18 177-184,1993. 

Pellerin, L. Lactate as a pivotal element in neuron-glia metabolic cooperation. Neurochem. Int. 43 331-338, 2003. 

Rhodospirillum rubrum SI Chemostat with glutamate limitation, D=0.013 h l, lactate, light saturation 20 0.26 65 Zurrer, Bachofen, 1979... 

A different approach is the combination of a Pt-carbonyl-cluster with a special dye, Safranine O (Saf 3,7-diamino-2,8-dimethyl-5-phenylphenazinium) in an aqueous/organic two-phase system [48]. The dye is reduced in the organic phase and subsequently, in a type of phase-transfer catalysis, it reduced the cofactor in the aqueous phase. In this example l-LDH is used as a production enzyme, reducing pyruvate to L-lactate (Scheme 43.6). Complete conversion was obtained within 48 h, the mixture containing pyruvate, NAD+ and the Pt-cluster catalyst in a 600 10 1 molar ratio. The TOF for NAD+ was 15 h-1. 

The deracemization of lactate, in principle, is also interesting. In this process, pyruvate is reduced at the cathode to racemic lactate which is reoxidized to pyruvate by the cheap L-lactate dehydrogenase combined with the anodic... 

Fig. 5. Coupled electrochemical process for the formation of D-lactate from pyruvate (l-LDH = L-lactate dehydrogenase)...

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