Carnitine other conditions

The genetically determined defect of membrane carnitine transport is the only known condition that fulfills the criteria for primary carnitine deficiency [4, 9]. This condition, like the other conditions involving the carnitine cycle, is not associated with dicarboxylic aciduria. It is... 

Other conditionally essential amino acids, such as cysteine, carnitine, and glutamine, are not included because they are unstable or insoluble. Cysteine and carnitine are commonly added to PN solutions compounded for newborns. 

When the enantioselective reduction of ethyl 4-chloroacetoacetate was carried out with alcohol dehydrogenase from Candida parapsilosis, the other enantiomer was produced ethyl (P)-4-chloro-3-hydroxybutanoate [134]. This product is a key intermediate in a synthesis of (R)-carnitine. In this case a substrate coupled approach was chosen. The enzyme also has a strong oxidation activity for 2-propanol, which was therefore selected as the cosubstrate. The situation is depicted in Fig. 3.50. Under optimized conditions, the yield of (R)-ethyl-4-chloro-3-hydroxy-butanoate reached 36.6 g L-1 (> 99% ee, 95% yield) on a 30 L scale. 

Fatty acids are the major fuel for red muscle fibers, which are the main type involved in moderate exercise. Children who lack one or the other of the enzymes required for carnitine synthesis, and are therefore reliant on a dietary intake, have poor exercise tolerance, because they have an impaired ability to transport fatty acids into the mitochondria for /S - oxidation. Provision of supplements of carnitine to the affected children overcomes the problem. Extrapolation from this rare clinical condition has led to the use of carnitine as a so-called ergogenic aid to improve athletic performance. 

Several commercially available CAA solutions are designed to provide conditionally essential amino acids (CEAAs). CEAAs are considered nonessential during health because they are produced from other amino acids. However, under certain physiologic conditions such as prematurity or sepsis, these amino acids cannot be synthesized in sufficient quantities. CAA solutions specifically designed for use in neonates and pediatric patients contain increased amounts of taurine, aspartic acid, and glutamic acid. Other CEAAs, such as cysteine, carnitine, and glutamine, are not available in commercial CAA solutions in pharmacologic amounts because they are relatively unstable or poorly soluble. ... 

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