Prokaryotic Expression Systems

Kineret is the tradename given to a recently approved product based on the latter strategy. Indicated in the treatment of rheumatoid arthritis, the product consists of a recombinant form of the human IL-1 receptor antagonist. The 17.3 kDa, 153 amino acid product is produced in engineered E. coli and differs from the native human molecule in that it is non-glycosylated and contains an additional N-terminal methionine residue (a consequence of its prokaryotic expression system). 

Although bacterial hosts can be useful for protein production, E. coli and other prokaryotic expression systems have some limitations. For example, they are incapable of posttranslational modifications such as glycosylation and as a consequence many eukaryotic proteins produced in prokaryotic expression systems are nonfunctional (Rai and Padh, 2001). However, in the case of most peptides, including self-assembling peptides, such modifications are currently not required. Of course, this limitation may have implications for future... 

Escherichia coli, 14, 15, 22, 241, 305-306 expression problems with, 8 heterologous expression investigation of, 3 prokaryotic expression systems and, 4-8... 

Procapsid/capsid structure, with herpes simplex virus 1 (HSV-1), 398 projectBjFile, 111, 112 Prokaryotic expression systems, 4-8 Escherichia coli and, 4—8 Protein folding, of influenza hemagglutinin (HA), 351-352... 

In prokaryotic expression systems, a conversion of mammalian codon use to bacterial codon use is an accepted and widely used concept. In general, highly expressed genes exhibit a codon bias towards more abundant tRNAs. However, few data are found in the literature on codon use when human genes are over-expressed in mammalian host cells. It is questionable that original exon sequences for all the desired proteins of interest will always provide a codon utilization that is compatible with high-level expression. In some cases, codon optimization has been shown to increase transgene expression dramatically in mammalian cells. A review of these studies has been provided by Makrides [66]. 

Alternative Prokaryotic Expression Systems. In addition to conditioning E. coli-strains to efficient secreters, alternative species, which are considered to inherently possess a superior secretion capacity, are tried to be established as expression... 

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