Solution structure of a circular-permuted variant of the potent HIV-inactivating protein cyanovirin-N: structural basis for protein stability and oligosaccharide interaction.


Abstract

The high-resolution solution structure of a monomeric circular permuted (cp) variant of the potent HIV-inactivating protein cyanovirin-N (CV-N) was determined by NMR. Comparison with the wild-type (wt) structure revealed that the observed loss in stability of cpCV-N compared to the wt protein is due to less favorable packing of several residues at the pseudo twofold axis that are responsible for holding the two halves of the molecule together. In particular, the N and C-terminal amino acid residues exhibit conformational flexibility, resulting in fewer and less favorable contacts between them. The important hydrophobic and hydrogen-bonding network between residues W49, D89, H90, Y100 and E101 that was observed in wt CV-N is no longer present. For instance, Y100 and E101 are flexible and the tryptophan side-chain is in a different conformation compared to the wt protein. The stability loss amounts to approximately 2kcal/mol and the mobility of the protein is evident by fast amide proton exchange throughout the chain. Mutation of the single proline residue to glycine (P52G) did not substantially affect the stability of the protein, in contrast to the finding for wtCV-N. The binding of high-mannose type oligosaccharides to cpCV-N was also investigated. Similar to wtCV-N, two carbohydrate-binding sites were identified on the protein and the Man alpha1-->2Man linked moieties on the sugar were delineated as binding epitopes. Unlike in wtCV-N, the binding sites on cpCV-N are structurally similar and exhibit comparable binding affinities for the respective sugars. On the basis of the studies presented here and previous results on high-mannose binding to wtCV-N, we discuss a model for the interaction between gp120 and CV-N. Study holds ProTherm entries: 15712, 15713 Extra Details: cyanovirin-N; circular permuted CV-N; high-mannose sugars; protein-carbohydrate interaction; gp120

Submission Details

ID: iVntDDR93

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:46 p.m.

Version: 1

Publication Details
Barrientos LG;Louis JM;Ratner DM;Seeberger PH;Gronenborn AM,J. Mol. Biol. (2003) Solution structure of a circular-permuted variant of the potent HIV-inactivating protein cyanovirin-N: structural basis for protein stability and oligosaccharide interaction. PMID:12473463
Additional Information

Structure view and single mutant data analysis

Study data

No weblogo for data of varying length.
Colors: D E R H K S T N Q A V I L M F Y W C G P
 

Data Distribution

Studies with similar sequences (approximate matches)

Correlation with other assays (exact sequence matches)


Relevant PDB Entries

Structure ID Release Date Resolution Structure Title
2RP3 2008-08-19 Solution Structure of Cyanovirin-N Domain B Mutant
2EZN 1999-05-11 SOLUTION NMR STRUCTURE OF CYANOVIRIN-N ENSEMBLE OF 40 SIMULATED ANNEALING STRUCTURES
2EZM 1999-05-11 SOLUTION NMR STRUCTURE OF CYANOVIRIN-N, RESTRAINED REGULARIZED MEAN COORDINATES
1J4V 2002-03-06 CYANOVIRIN-N
1L5E 2002-06-05 The domain-swapped dimer of CV-N in solution
1N02 2002-12-18 Solution Structure of a Circular-Permuted Variant of the Potent HIV-inactivating Protein Cyanovirin-N
1IIY 2001-10-24 Solution NMR Structure of Complex of 1:2 Cyanovirin-N:Man-Alpha1,2-Man-Alpha Restrained Regularized Mean Coordinates
3LHC 2010-02-09 1.34 Crystal structure of cyanovirin-n swapping domain b mutant
2RDK 2008-05-06 1.35 Five site mutated Cyanovirin-N with Mannose dimer bound
3CZZ 2008-08-19 1.36 Crystal structure of Cyanovirin-N domain B mutant
3EZM 1998-12-23 1.5 CYANOVIRIN-N
1LOM 2002-06-26 1.72 CYANOVIRIN-N DOUBLE MUTANT P51S S52P
3S3Z 2011-08-03 1.75 Crystal Structure an Tandem Cyanovirin-N Dimer, CVN2L10
2Z21 2007-07-31 1.8 Crystal Structure of a five site mutated Cyanovirin-N
2PYS 2007-07-31 1.8 Crystal Structure of a Five Site Mutated Cyanovirin-N with a Mannose Dimer Bound at 1.8 A Resolution
4J4C 2013-04-03 1.9 Structure of P51G Cyanovirin-N swapped dimer in the P3221 space group
4J4F 2013-04-03 1.9 Structure of P51G Cyanovirin-N swapped tetramer in the P212121 space group
4J4G 2013-04-03 1.92 Structure of P51G Cyanovirin-N swapped tetramer in the C2 space group
1L5B 2002-05-22 2.0 DOMAIN-SWAPPED CYANOVIRIN-N DIMER
4J4D 2013-04-03 2.0 Structure of P51G Cyanovirin-N swapped dimer in the P21212 space group
3S3Y 2011-08-03 2.0 Crystal Structure an Tandem Cyanovirin-N Dimer, CVN2L0
4J4E 2013-04-03 2.4 Structure of P51G Cyanovirin-N swapped trimer in the P212121 space group
3GXY 2009-05-05 2.4 Crystal structure of cyanovirin-n complexed to a synthetic hexamannoside
3GXZ 2009-04-14 2.5 Crystal structure of cyanovirin-n complexed to oligomannose-9 (man-9)

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
100.0 Cyanovirin-N P81180 CVN_NOSEL