The dependence of stability of the green fluorescent protein-obelin hybrids on the nature of their constituent modules and the structure of the aminoacid linker

Recombinant plasmids containing genes for the green fluorescent protein (GF P) from Aequorea victoria and the photoprotein obelin from Obelia longissim a linked in-frame by inserts differing in nucleotides sequences were constr ucted. The expression of the chimeric genes in Escherichia coli cells resul ted in synthesis of the GFP-obelin hybrid proteins. These proteins were pur ified to homogeneity and subjected to limited trypsinolysis. It was shown t hat the resistance of GFP-obelin hybrid proteins to trypsin depends on the nature of their constituent modules and the amino acid sequences of linkers between the modules. The kinetics of accumulation of full-length hybrid pr oteins during the growth of bacterial cells does not depend on the structur e of the peptide linkers. Most of the full-length product accumulates in ce lls in the form of inclusion bodies resistant to endogenous proteases. The soluble fraction of the protein undergoes considerable proteolysis regardle ss of the linker structure.