Acinetobacter calcoaceticus possesses an L(+)-lactate dehydrogenase and a D(-)-lactate dehydrogenase. Results of experiments in which enzyme activities were measured after growth of bacteria in different media indicated that the two enzymes were co-ordinately induced by either enantiomer of lactate but not by pyruvate, and repressed by succinate or L-glutamate. The two lactate dehydrogenases ha...

Lactate dehydrogenase isoenzymes were partially separated by use of a previously described column technique for creatine kinase [Clin. Chem. 20, 36 (1974)]. Extracts of lactate dehydrogenase-rich tissues were used to evaluate column resolution. Samples layered on mini-columns containing DEAE-Sephadex were eluted with Tris-buffered sodium chloride (100 and 200 mmol/liter). Lactate dehydrogenase ...

1. The contents of dihydroxyacetone phosphate, fructose diphosphate, pyruvate and lactate and the activities of aldolase and lactate dehydrogenase in the liver, kidney, testis, skeletal muscle, blood cells, sarcoma and hepatoma of rats were measured. 2. Correlations were established between components of the glycolytic pathway as follows: activities of aldolase and lactate dehydrogenase; conten...

The number of lactate dehydrogenase molecules per cell equivalent in normal adult mouse tissues is: heart muscle 1.13 x 10s, skeletal muscle 3.6 x 1O8, liver 3.94 x lo’, and kidney 3.91 x 107. These steady state levels of lactate dehydrogenase reflect a balance between synthesis and degradation. To study the relative role of the two processes the half-lives of lactate dehydrogenase in these fou...

In mitochondria-enriched preparations of human skeletal muscle, the measurement of pyruvate dehydrogenase activity, as determined by conventional spectrophotometric assay of NADH accumulation, is underestimated due to the oxidizing activity of the contaminating lactate dehydrogenase. Using a model reaction system consisting of varying mixtures of purified lactate and pyruvate dehydrogenases, we...

The changes in conformation of F-actin induced by the binding of the glycolytic enzyme lactate dehydrogenase were studied in myosin-free single ghost muscle fibres. The formation of the lactate dehydrogenase-F-actin complex was accompanied by changes in the parameters of intrinsic (tryptophan) and extrinsic (rhodaminyl-phalloin) polarized fluorescence of ghost muscle fibre F-actin. Lactate dehy...

A lactate dehydrogenase activity is present in rice (Oryza sativa L.) seedlings and roots. Under aerobic conditions, lactate dehydrogenase activity is barely detectable in rice seedlings and is very low in rice roots. In 30 day old roots, the activity is increased two to three times by an anoxic or hypoxic treatment and can be detected on immunoblots by an antiserum raised against barley lactat...

Leuconostoc mesenteroides increased its lactic acid production from glucose threefold when malic acid was added to the culture. This increase resulted also in a reduction of the ratio of d-lactic acid to l-lactic acid (31.5 to 1.23). Addition of malic acid increased 6.5-fold the specific activity of nicotinamide adenine dinucleotide (NAD)-linked l-lactate dehydrogenase and increased 3.2-fold th...

OBJECTIVE Altered mental status is a common cause of intensive care unit admission in children. Differentiating structural causes of altered mental status from metabolic etiologies is of utmost importance in diagnostic approach and management of the patients. Among many biomarkers proposed to help stratifying patients with altered mental status, spinal fluid lactate dehydrogenase appears to be ...