Recombinant porcine somatotropin

Porcine somatotropin and poultry somatotropin are both under development for use in swine and poultry. Recombinantly produced porcine somatotropin has been found to enhance performance dramatically. Increases in protein deposition, decreases in fat deposition, and depression of voluntary feed intake after injections of recombinant porcine somatotropin have been found across breeds. 

McLean, E., Donaldson, E. M., Mayer, I., Teskeredzic, E., Teskeredzic, Z., Pitt, C., and Souza, LM., 1994, Evaluation of a sustained-release polymer encapsulated form of recombinant porcine somatotropin upon long-term growth performance of Coho salmon, Oncorhynchns kisutch, Aquaculturel22 359- i6i. 

Blokland, M.H. Sterk, S.S. van Ginkel, LA. Stephany, R.W. Heck, AJ.R. Analysis for endogenous and recombinant porcine somatotropine in serum, Anal.Chim.Acta, 2003,483, 201-206. 

Some of these compounds could be considered as dietary additives, but various other terms, including pesticides, can also be used. They can have beneficial effects on the environment and this aspect will be discussed later. The ionophore monensin, which is an alicyclic polyether (Figure 1), is a secondary metabolite of Streptomyces and aids the prevention of coccidiosis in poultry. Monensin is used as a growth promoter in cattle and also to decrease methane production, but it is toxic to equine animals. " Its ability to act as an ionophore is dependent on its cyclic chelating effect on metal ions. ° The hormones bovine somatotropin (BST) and porcine somatotropin (PST), both of which are polypeptides, occur naturally in lactating cattle and pigs, respectively, but can also be produced synthetically using recombinant DNA methods and administered to such animals in order to increase milk yields and lean meat production. "... 

This renaturation procedure may find wider application to the commercial-scale renaturation of other recombinant proteins from bacterial inclusion bodies. The only proviso appears to be the existence of one or possibly more partially folded states at intermediate denaturant concentrations. Structural homologs of BST such as porcine somatotropin (16) and bovine prolactin are candidates for this approach to refolding. We are currently developing a general model for the prediction of optimum denaturant concentration for protein refolding via a consideration of the tradeoffs between aggregation and unfolding phenomena. 

Tsuji K, Baczynskyj L, Bronson G E (1992). Capillary electrophoresis-electrospray mass spectrometry for the analysis of recombinant bovine and porcine somatotropins. Analyt. Chem. 64 1864-1870. 

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