Recombinant expression of sericin-cecropin fusion protein and its functional activity

Enhanced antioxidant properties of sericin-cecropin fusion protein against oxidative stress in human adult dermal fibroblasts

“…Fusion of spider silk with human antimicrobial peptides, HNP 2 & 4 and hepcidin have resulted in a new chimeric protein with strong microbicidal and anti-cytotoxic properties. 30 The sericin-cecropin B fusion protein, demonstrated enhanced and broad spectrum antibacterial, 17 cell proliferative and cryoprotective functions 18 and in the present study with a strong antioxidant property. Further, the generation of recombinant fusion of functionalized biopolymer eliminates the use of chemical cross-linking, which leads to protein denaturation and residual toxicity.…”

“…In our work, partial ser1 sequence coding for 94 amino acids containing one copy of 38-amino acid motif, two copies of decapeptide repeat, SGGSSTYGYS, a SAGSSTEGYS repeat and serine-rich sequence are used for the successful expression of sericin alone and its fusion with cecropin B in E. coli . 17 The molecular masses are 12 and 16 kDa including histidine tags for sericin and sericin-cecropin B hybrid proteins, respectively. The sericin sequence we selected has a high content of polar amino acids, 36.2% serine, 17% threonine, and 5.3% tyrosine, close to the average amino acid composition of whole ser1 protein.…”

“…Recombinant sericin and its fusion protein with molecular mass of 12 and 16 kDa, respectively, previously expressed in Rosetta (DE3) was used in the study. 17 Briefly, a 282 bp ser1 sequence that includes the 38-amino acid repeat motif and two copies of the decapeptide sequence either alone or fused with the open reading frame (ORF) of cecropin B was expressed in bacteria to obtain sericin and sericin-cecropin B proteins. Extraction and purification of the recombinant proteins were carried out as follows: bacterial cells post IPTG induction were collected and resuspended in 1.5 mL lysis buffer (100 mM NaH 2 PO 4 , 10 mM Tris base, 8 M urea, 20 mM imidazole, pH 8.0).…”

“…14,15 Further, natural sericin obtained from the processing of cocoons is contaminated with heavy metals and other impurities that are toxic to cells which limits its applications. 16 To generate pure and multifunctional sericin protein as a novel biopolymer that could meet the stringent requirements of various biomedical applications, recombinant expression of sericin-cecropin B fusion was carried out by us for the first time and found antibacterial, 17 cell proliferative and cryoprotective properties. 18 The reason to choose cecropin B as fusion partner for sericin was, besides being a strong antimicrobial peptide, it is widely used in therapeutics, animal drugs and food preservatives.…”

Silk proteins in reconstructive surgery: Do they possess an inherent antibacterial activity? A systematic review

“…The other two articles attributed an inherent antibacterial property to SF. The silk proteins in these studies were from transgenic silkworms 13,53 . Both studies took advantage of the antimicrobial peptide cecropin, which is naturally secreted by the silkworm to defend against pathogens.…”