Characterization of silk proteins from lepidopteran species

Silk protein isolation, microsequencing, cDNA library screening with oligonucleotides as well as differential screening allowed us to isolate the main structural components of Galleria mellonella silk. Most of the genes we characterized have also highly diverged counterparts in Bombyx mori. We show that Galleria fibroin has unique arrangement of repetitive units causing its enormous strength and elasticity. We also found that silk further contains several low molecular weight proteins that are not essential for the silk structure but may provide protection against predators, molds, and microbes. We described a novel protein called seroin and two proteinase inhibitors that are secreted into the silk of both Galleria mellonella and Bombyx mori.


 

We use following model organisms for silk studies:
 
Galleria mellonella (waxmoth)
last larval instar larva - cocoon - adult moth

Antheraea yamamai (japanese oak tree silkworm)
last larval instar eggs - larva - cocoon

 
 
 
 

Selected publications and posters:

Zurovec M. and Sehnal F. (2002) Unique molecular architecture of silk fibroin in the waxmoth, Galleria mellonella. J Biol Chem. PMID: 11886872   - load reprint in pdf format

Nirmala X., Kodrík D., Zurovec M. and Sehnal F. (2001) Insect silk contains both a Kunitz type and a unique Kazal-type proteinase inhibitors, Eur. J. Biochem. 268: 2064-2073. PMID: 11277929   - load reprint in pdf format

Nirmala X., Mita K., Vanishree V., Zurovec M., Sehnal F.  (2001) Identification of four small molecular mass proteins in the silk of Bombyx mori. Insect Molecular Biology 10: 437-445. PMID: 11881808   - load reprint in pdf format

Zurovec M and Sehnal F. (2001) Unusual fibroin structure in the waxmoth, Galleria mellonella: Implications for fibre formation. ESF Network on Silk: Properties and Production, Workshop "Assembly, Structure and Properties of Fibrous Proteins with Emphasis on Silk". Villa Olmo, Como (Italy), October 19-21

Zurovec M., Yang C. Kodrik D., Sehnal F. (1998) Identification of a novel type silk protein and regulation of its expression. J. Biol. Chem. 273: 15423-15428. PMID: 9624126  - load reprint in pdf format