Skip Navigation

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Request Permissions
Google Scholar
Right arrow Articles by YAMASHITA, T.
Right arrow Articles by MIMURA, T. H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by YAMASHITA, T.
Right arrow Articles by MIMURA, T. H.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

J. Biochem, 1974, Vol. 76, No. 6 1337-1342
© 1974 Japanese Biochemical Society

research-article

Local Conformational Change of Myosin Detected by Tryptic Digestibility

II. Effect of Magnesium Ions on the Fragmentation Pattern of Heavy Meromyosin by Trypsin

Tatsuhisa YAMASHITA and Toshiko HASUMI MIMURA*

Department of Biochemistry, School of Medicine, Juntendo University Bunkyo-ku, Tokyo 113

In order to detect the local conformational changes in the heavy meromyosin (HMM) molecule induced by magnesium ions, which have been suggested by the decrease in the ATPase [EC 3.6.1.3 [EC] ] activity of HMM caused by tryptic digestion, HMM with minimum cleavage of the intramolecular peptide bond, prepared by tryptic proteolysis at pH 6.4, was digested with trypsin [EC 3.4.21.4 [EC] ] at pH 7.6 in the presence or absence of Mg ions. The following results were obtained.

  1. The gel filtration pattern indicated that HMM subfragment-1 (HMM S-1) was obtained from HMM by tryptic digestion in the absence of Mg ions, but not in their presence. These results were not affected by the addition of substrate or analogues such as ATP, ITP, ADP, and PP1, or by the addition of actin.
  2. SDS-polyacrylamide gel electrophoresis revealed that on tryptic digestion without the divalent cation, the large polypeptide chains contained in HMM were promptly degraded to form smaller peptides, while the presence of Mg ions almost completely prevented the formation of the peptide of approximately 4.2–4.5×10–4 daltons.
  3. The identification of the small peptides suggests the presence of flexible regions susceptible to trypsin, which are made rigid by Mg ions, in HMM S-1 and the linking part between HMM S-1 and HMM S-2.

*Present address: Teikyo University School of Medicine, Itabashi-ku, Tokyo.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.