Role of electrostatic interactions in defining the potency of neurotoxin B-IV from Cerebratulus lacteus.

The Journal of Biological Chemistry
P H Wen, K M Blumenthal

Abstract

Chemical modification implicates arginine residues of the Cerebratulus lacteus neurotoxin B-IV in biological activity. In the present study, we used site-directed mutagenesis to assess the functional contributions of each of these residues. Panels of mutants at each site have been constructed by polymerase chain reaction and recombinant proteins expressed and purified to homogeneity using an Escherichia coli expression system developed in this laboratory. All substitutions for Arg-17 (Gln, Ala, or Lys) yield proteins having undetectable levels of activity, while charge neutralizing replacement of Arg-25 (R25Q) causes a 400-fold reduction in specific toxicity. However, the R25K mutein is almost as active as natural toxin. Circular dichroism spectroscopy indicates that there are no major conformational changes in any of these muteins. These results therefore demonstrate the requirement for a guanidinium group at position 17, and a positive charge at position 25. NMR analyses (Hansen, P. E., Kem, W. R., Bieber, A. L., and Norton, R. S. (1992) Eur. J. Biochem. 210, 231-240) reveal neurotoxin B-IV to contain two antiparallel alpha-helices, which together include 57% of the sequence. Both Arg-17 and Arg-25 lie on the same face of the...Continue Reading

References

Jan 1, 1978·Annual Review of Biochemistry·P Y Chou, G D Fasman
Apr 1, 1992·Toxicon : Official Journal of the International Society on Toxinology·M Fainzilber, E Zlotkin
Jan 1, 1991·Toxicon : Official Journal of the International Society on Toxinology·R S Norton
Dec 5, 1991·European Journal of Biochemistry·M FainzilberE Zlotkin
Jan 1, 1986·Annual Review of Biochemistry·W A Catterall
May 5, 1986·Journal of Molecular Biology·F W Studier, B A Moffatt
Jan 1, 1986·Toxicon : Official Journal of the International Society on Toxinology·K M Blumenthal
May 1, 1972·Toxicon : Official Journal of the International Society on Toxinology·E ZlotkinS Lissitzky
Jan 1, 1980·Annual Review of Pharmacology and Toxicology·W A Catterall
Sep 15, 1981·Biochemistry·M M TeeterJ J L'Italien
Mar 5, 1993·Journal of Molecular Biology·M M TeeterN H Heo
Sep 1, 1995·Protein Science : a Publication of the Protein Society·M SukumarL M Gierasch

❮ Previous
Next ❯

Citations

Feb 20, 2019·Toxins·Ulf GöranssonHåkan S Andersson

❮ Previous
Next ❯

Related Concepts

Related Feeds

ASBMB Publications

The American Society for Biochemistry and Molecular Biology (ASBMB) includes the Journal of Biological Chemistry, Molecular & Cellular Proteomics, and the Journal of Lipid Research. Discover the latest research from ASBMB here.