A study of human furin specificity using synthetic peptides derived from natural substrates, and effects of potassium ions

Abstract

We explored furin substrate requirements in addition to the motif R-X-K/R-R using synthetic fluorescent resonance energy transfer (FRET) decapeptides. These decapeptides were derived from furin cleavage sites in viral coat glycoproteins and human and bacterial protein precursors. The hydrolysis by furin of most substrate was activated by K+ ion, whereas kosmotropic anions of the Hofmeister series were inhibitors. The analysis of furin hydrolytic activity showed that its efficiency is highly dependent on the particular combinations of amino acids at different substrate positions. There is a clear interdependence of furin subsites that must be taken in account in determining its specificity and also for the design of inhibitors. However, clear preferences were detected for substrates with S at P′1, and V at P′2, at P′3 the amino acids D, S, L and A are almost equally frequent. In the non-prime subsites the best substrates presented S and H at P6; basic amino acids at P5; and no clear tendency at P3. Interestingly, two amino acid substitutions on the prime side of the peptide derived from H5N1 influenza hemagglutinin furin processing site highly improved its hydrolysis. These modifications are possible by single point mutations, suggesting a potential yield of a more infectious virus.

Cleavage efficient 2A peptides for high level monoclonal antibody expression in CHO cells

“…Cleavage efficiency at the furin and 2A recognition sites are both affected by the expressed proteins and the amino acids immediately surrounding their respective recognition sites. 33,35,43,44 P2A was reported to have the highest cleavage efficiency compared to the other 3 2A peptide in a previous study. 32 The low cleavage efficiency of P2A observed in this work could be due to the nature of HC and LC polypeptides.…”

Whole-Genome Sequencing Coupled to Imputation Discovers Genetic Signals for Anthropometric Traits

“…3,6.17] with scores above zero indicating constraint (colored in white for scores < 0 and in shades of orchid for scores > 0). (Table S14) 58 We also undertook fine mapping 28 of 186 anthropometric trait loci established in the literature which also reached p % 5 3 10 À8 in the discovery stage (Table S4). We find that 14 credible sets 95% likely to contain the causal variant are narrowed down to a single variant, and 6 are narrowed down to 2 causal variants (Table S23).…”

Construction and Characterization of Novel, Recombinant Immunotoxins Targeting the Her2/neu Oncogene Product: In vitro and In vivo Studies

“…1A). Several biochemical studies have shown that the serine protease furin efficiently cleaves proteins containing these recognition sequences (29,30).…”

“…Furin is a cellular endoprotease and has been implicated in the proteolytic activation of large numbers of secreted proteins (29,30). Inclusion of furin-cleavable linkers in fusion constructs containing ribotoxin, caspase-3, or granzyme B has resulted in a significant improvement in specific toxicity compared with constructs containing stable linkers (42,43).…”