Expanding the family of collagen proteins: recombinant bacterial collagens of varying composition form triple-helices of similar stability.
The presence of the (Gly-Xaa-Yaa)(n) open reading frames in different bacteria predicts the existence of an expanded family of collagen-like proteins. To further explore the triple-helix motif and stabilization mechanisms in the absence of hydroxyproline (Hyp), predicted novel collagen-like proteins from Gram-positive and -negative bacteria were expressed in Escherichia coli and characterized. Soluble proteins capable of successful folding and in vitro refolding were observed for collagen proteins from Methylobacterium sp 4-46, Rhodopseudomonas palustris and Solibacter usitatus . In contrast, all protein constructs from Clostridium perfringens were found predominantly in inclusion bodies. However, attachment of a heterologous N-terminal or C-terminal noncollagenous folding domain induced the Clostridium perfringens collagen domain to fold and become soluble. The soluble constructs from different bacteria had typical collagen triple-helical features and showed surprisingly similar thermal stabilities despite diverse amino acid compositions. These collagen-like proteins provide a resource for the development of biomaterials with new properties.
Xu
Chunying
C
Department of Biochemistry, University of Medicine and Dentistry of New Jersey, Piscataway, 08854, USA.
Yu
Zhuoxin
Z
Inouye
Masayori
M
Brodsky
Barbara
B
Mirochnitchenko
Oleg
O
D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000737:chemistry*; D003094:Collagen / Q000096:biosynthesis* / Q000737:chemistry*; D017510:Protein Folding; D055550:Protein Stability; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry
D001426:Bacterial Proteins; D011994:Recombinant Proteins; D003094:Collagen