Structural Model for the Spider Silk Protein Spidroin-1

Autor(es)

Aparecido dos Santos-Pinto, Jose Roberto ^{[1, 2]} ; Arcuri, Helen Andrade ^[2] ; Priewalder, Helga ^[3] ; Salles, Heliana Clara ^[2] ; Palma, Mario Sergio ^[2] ; Lubec, Gert ^[1]

Afiliação do(s) autor(es)

^[1] Med Univ Vienna, Dept Pediat, A-1090 Vienna - Austria

^[2] Sao Paulo State Univ, Ctr Study Social Insects, Inst Biosci Rio Claro, Dept Biol, BR-13500 Rio Claro, SP - Brazil

^[3] Geol Survey Austria, Dept Paleontol, A-1230 Vienna - Austria

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF PROTEOME RESEARCH; v. 14, n. 9, p. 3859-3870, SEP 2015.
• Citações Web of Science: 7

Resumo

Most reports about the 3-D structure of spidroin-1 have been proposed for the protein in solid state or for individual domains of these proteins. A gel-based mass spectrometry strategy using collision-induced dissociation (CID) and electron-transfer dissociation (ETD) fragmentation methods was used to completely sequence spidroins-1A and -1B and to assign a series of post-translational modifications (PTMs) on to the spidroin sequences. A total of 15 and 16 phosphorylation sites were detected on spidroin-1A and -1B, respectively. In this work, we present the nearly complete amino acid sequence of spidroin-1A and -1B, including the nonrepetitive N- and C-terminal domains and a highly repetitive central core. We also described a fatty acid layer surrounding the protein fibers and PTMs in the sequences of spidroin-1A and -1B, including phosphorylation. Thus, molecular models for phosphorylated spidroins were proposed in the presence of a mixture fatty acids/water (1:1) and submitted to molecular dynamics simulation. The resulting models presented high content of coils, a higher percentage of alpha-helix, and an almost neglected content of 3(10)-helix than the previous models. Knowledge of the complete structure of spidroins-1A and -1B would help to explain the mechanical features of silk fibers. The results of the current investigation provide a foundation for biophysical studies of the mechanoelastic properties of web-silk proteins. (AU)

• Processo FAPESP: 10/19051-6 - Análise Estrutural das proteínas da seda da teia da aranha Nephila clavipes por abordagem proteômica.
• Beneficiário: José Roberto Aparecido dos Santos-Pinto
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 13/26451-9 - Bioprospecção e Análise Estrutural das Proteínas da Seda de Artrópodes por uma Abordagem Proteômica Utilizando um Sistema nanoLC-ESI-CID/ETD
• Beneficiário: José Roberto Aparecido dos Santos-Pinto
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 11/51684-1 - Biologia de sistemas como estratégia experimental para a descoberta de novos produtos naturais na fauna de artrópodes peçonhentos do Estado de São Paulo
• Beneficiário: Mario Sergio Palma
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOTA - Temático