الفهرس 
GENERAL INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
CGP is like all other homopolyamides of natural origin produced independently of the ribosomal protein synthesis apparatus and independently of an RNA template. Therefore, cyanophycin synthesis is resistant to a large variety of antibiotics which affect protein biosynthesis like chloramphenicol, erythromycin, streptomycin, tetracycline and rifampicin (Simon, 1976). As a product of a template-independent biosynthesis process (reviewed by Stubbe et al., 2005), cyanobacterial CGP exhibits a high degree of polydispersity corresponding to a molecular mass distribution which ranges from 25 to 100 kDa. In contrast, CGP synthesized by cells of Acinetobacter sp. strain ADP1 (Krehenbrink and Steinbüchel, 2004) as well as CGP produced in recombinant bacteria showed a markedly lower dispersity (22–43 kDa). In recent studies, Allen et al. (2005) found low molecular mass CGP (30–60 kDa) also in cells of Synechocystis sp. strain PCC6308. The CGP was extended rather than de novo synthesized during 24 hour of incubation yielding CGP molecules of apparent masses of up to approximately 100 kDa. The observed mass differences may be due to (1) the absence of a further catalytic or regulatory factor in recombinant bacteria as well as in Acinetobacter or (2) differences in the enzyme-to-substrate ratio in these cells (Aboulmagd et al., 2000).