Analysis of active site residues of the antiviral protein from summer leaves from Phytolacca americana by site-directed mutagenesis.
Details
Serval ID
serval:BIB_A743D714F369
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Analysis of active site residues of the antiviral protein from summer leaves from Phytolacca americana by site-directed mutagenesis.
Journal
Biochemical and Biophysical Research Communications
ISSN
0006-291X[print], 0006-291X[linking]
Publication state
Published
Issued date
12/1998
Volume
253
Number
3
Pages
582-587
Language
english
Notes
Publication types: Journal Article
Publication Status: ppublish
Publication Status: ppublish
Abstract
The summer leaf isoform of the pokeweed (Phytolacca americana) antiviral protein, PAP II, was produced in high yields from inclusion bodies in recombinant E. coli. On the basis of its sequence similarity with the spring leaf isoform (PAP I) and with the A chain of ricin, a three-dimensional model of the protein was constructed as an aid in the design of active site mutants. PAP II variants mutated in residues Asp 88 (D88N), Tyr 117 (Y117S), Glu 172 (E172Q), Arg 175 (R175H) and a combination of Asp 88 and Arg 175 (D88N/R175H) were produced in E. coli and assayed for their ability to inhibit protein synthesis in a rabbit reticulocyte lysate. All of these mutations had effects deleterious to the enzymatic activity of PAP II. The results were interpreted in the light of three reaction mechanisms proposed for ribosome-inactivating proteins (RIPs). We conclude that none of the proposed mechanisms is entirely consistent with the data presented here.
Keywords
Amino Acid Sequence, Animals, Antiviral Agents/chemistry, Antiviral Agents/metabolism, Catalytic Domain/genetics, Cell-Free System, Dose-Response Relationship, Drug, Isoenzymes/genetics, Isoenzymes/metabolism, Models, Molecular, Molecular Sequence Data, Mutagenesis, Site-Directed, N-Glycosyl Hydrolases/chemistry, N-Glycosyl Hydrolases/genetics, Plant Proteins/chemistry, Plant Proteins/genetics, Protein Biosynthesis/drug effects, Rabbits, Reticulocytes, Ribosome Inactivating Proteins, Type 1, Seasons, Sequence Homology, Amino Acid
Pubmed
Web of science
Create date
24/01/2008 15:39
Last modification date
20/08/2019 15:12