Penicillin growth stimulation

Bicillin benzathin penicillin, bicozamycin [inn] is a diketopiperazine antibiotic. It can be used as an ANTIBACTERIAL antiinfective agent for gut infections, and commercially as a growth stimulant for chickens and swine. 

Barnes, R. H., Fiala, G., and Kwong, E., 1965b, Prevention of coprophagy in the rat and the growth stimulating effects of methionine, cystine, and penicillin when added to diets containing unheated soybeans, J. Nutr., 85 127-131. 

Valine A branched-chain essential amino add that has stimulant activity. It promotes muscle growth and tissue repair. It is a precursor in the penicillin biosynthetic pathway. [NIH]... 

Penicillin Inhibits root and shoot growth and stimulator in Renulex taamle... 

Feedback Regulation. Feedback regulation also appears to play a role in secondary metabolism. It was shown many years ago that chloramphenicol inhibits its own production at concentrations nontoxic for growth of Streptomyces venezuelae (Legator and Gottlieb, 1953). Addition of 6-methylsalicylic acid to idiophase mycelium of P. urticae inhibits its own synthesis (Bu Lock and Shepherd, 1968). Stimulation of carotenoid overproduction by )8-ionone in Phycomyces blakesleeanus appears to be due to its ability to interfere with normal feedback inhibition (Reyes et al, 1964). The inhibition of penicillin production by lysine (Demain, 1957) seems to be due to feedback regulation by the amino acid of a branched pathway (Fig. 6) leading to both lysine and... 

In addition to the penicillins and cephalosporins, many other substances with antibiotic properties are known and widely used. Substances in this group include the tetracyclines, chloramphenicol and thiamphenicol, aminoglycosides, polymyxins, rifamycins, macrolides, lincomycins, and other miscellaneous compounds. These antibiotics are used in the systemic and topical treatment of infectious diseases. Some of these antibiotics have also been used to stimulate growth in animals they may still be in use now and may therefore persist in the environment. 

Induced cells contain a mechanism for concentrating inducers within the cells, and this mechanism appears to play a part in the induction process. The formation of enzyme depends on the continued presence of inducer. The rate of enzyme synthesis with adequate amoimts of inducer is proportional to the growth of the bacteria. When the inducer is removed (by suspending the centrifuged bacteria in fresh medium), enzyme synthesis stops abruptly. The enzyme already formed, however, is stable, and persists unchanged for many generations. Sulfur-labeled amino acids have been used to demonstrate that the induced enzyme is formed directly from free amino acids, and that proteins already in the bacteria do not contribute amino acids to the new enzyme. In the absence of the inducer, the adaptive enzyme retains its label. Some properties of inducers were found in a study of penicillinase production by BadUus cereusJ With this system it was shown that in a brief exposure a small amount of penicillin is specifically bound within the cells, and is not hydrolyzed, but stimulates the production of several equivalents of penicillinase. 

Figure 6.16 Flow chart for the development of a large-scale industrial fermentation. The organism, in this case Penicillium chrysogenum, is grown up in stages from the stored organism, in this case lyophilized spores, until there is enough growth to inoculate the production fermenter. Only at this stage is the production of the metabolite, here penicillin, stimulated...

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