Skip to main content
Protein Science : A Publication of the Protein Society logoLink to Protein Science : A Publication of the Protein Society
. 1998 Dec;7(12):2653–2658. doi: 10.1002/pro.5560071219

Selective and asymmetric action of trypsin on the dimeric forms of seminal RNase.

C De Lorenzo 1, F Dal Piaz 1, R Piccoli 1, A Di Maro 1, P Pucci 1, G D'Alessio 1
PMCID: PMC2143891  PMID: 9865960

Abstract

Dimeric seminal RNase (BS-RNase) is an equilibrium mixture of conformationally different quaternary structures, one characterized by the interchange between subunits of their N-terminal ends (the MXM form); the other with no interchange (the M=M form). Controlled tryptic digestion of each isolated quaternary form generates, as limit digest products, folded and enzymatically active molecules, very resistant to further tryptic degradation. Electrospray mass spectrometric analyses and N-terminal sequence determinations indicate that trypsin can discriminate between the conformationally different quaternary structures of seminal RNase, and exerts a differential and asymmetric action on the two dimeric forms, depending on the original quaternary conformation of each form. The two digestion products from the MXM and the M=M dimeric forms have different structures, which are reminiscent of the original quaternary conformation of the dimers: one with interchange, the other with no interchange, of the N-terminal ends. The surprising resistance of these tryptic products to further tryptic action is explained by the persistence in each digestion product of the original intersubunit interface.

Full Text

The Full Text of this article is available as a PDF (1.6 MB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Arnold U., Rücknagel K. P., Schierhorn A., Ulbrich-Hofmann R. Thermal unfolding and proteolytic susceptibility of ribonuclease A. Eur J Biochem. 1996 May 1;237(3):862–869. doi: 10.1111/j.1432-1033.1996.0862p.x. [DOI] [PubMed] [Google Scholar]
  2. D'Alessio G., Malorni M. C., Parente A. Dissociation of bovine seminal ribonuclease into catalytically active monomers by selective reduction and alkylation of the intersubunit disulfide bridges. Biochemistry. 1975 Mar 25;14(6):1116–1122. doi: 10.1021/bi00677a004. [DOI] [PubMed] [Google Scholar]
  3. Di Donato A., Galletti P., D'Alessio G. Selective deamidation and enzymatic methylation of seminal ribonuclease. Biochemistry. 1986 Dec 30;25(26):8361–8368. doi: 10.1021/bi00374a005. [DOI] [PubMed] [Google Scholar]
  4. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  5. Mazzarella L., Capasso S., Demasi D., Di Lorenzo G., Mattia C. A., Zagari A. Bovine seminal ribonuclease: structure at 1.9 A resolution. Acta Crystallogr D Biol Crystallogr. 1993 Jul 1;49(Pt 4):389–402. doi: 10.1107/S0907444993003403. [DOI] [PubMed] [Google Scholar]
  6. Parente A., Branno M., Malorni M. C., Welling G. W., Libonati M., D'Alessio G. Proteolytic enzymes as structural probes for ribonuclease BS-1. Biochim Biophys Acta. 1976 Sep 14;445(2):377–385. doi: 10.1016/0005-2744(76)90091-7. [DOI] [PubMed] [Google Scholar]
  7. Piccoli R., Tamburrini M., Piccialli G., Di Donato A., Parente A., D'Alessio G. The dual-mode quaternary structure of seminal RNase. Proc Natl Acad Sci U S A. 1992 Mar 1;89(5):1870–1874. doi: 10.1073/pnas.89.5.1870. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Tamburrini M., Piccoli R., De Prisco R., Di Donato A., D'Alessio G. Fast and high-yielding procedures for the isolation of bovine seminal RNAase. Ital J Biochem. 1986 Jan-Feb;35(1):22–32. [PubMed] [Google Scholar]

Articles from Protein Science : A Publication of the Protein Society are provided here courtesy of The Protein Society

RESOURCES