scholarly journals A Single Amino Acid Deletion in the Matrix Protein of Porcine Reproductive and Respiratory Syndrome Virus Confers Resistance to a Polyclonal Swine Antibody with Broadly Neutralizing Activity

2015 ◽  
Vol 89 (12) ◽  
pp. 6515-6520 ◽  
Author(s):  
Benjamin R. Trible ◽  
Luca N. Popescu ◽  
Nicholas Monday ◽  
Jay G. Calvert ◽  
Raymond R. R. Rowland

Assessment of virus neutralization (VN) activity in 176 pigs infected with porcine reproductive and respiratory syndrome virus (PRRSV) identified one pig with broadly neutralizing activity. A Tyr-10 deletion in the matrix protein provided escape from broad neutralization without affecting homologous neutralizing activity. The role of the Tyr-10 deletion was confirmed through an infectious clone with a Tyr-10 deletion. The results demonstrate differences in the properties and specificities of VN responses elicited during PRRSV infection.

1988 ◽  
Vol 168 (6) ◽  
pp. 2045-2057 ◽  
Author(s):  
F Gotch ◽  
A McMichael ◽  
J Rothbard

CTL specific for the influenza A virus matrix peptide 57-68 and restricted by HLA-A2 were studied. Their ability to recognize a set of analogue peptides, each of which differed from the natural peptide by a single amino acid, was analyzed. This revealed a core of five amino acids, 61-65, where one or more changes completely abrogated recognition. The glycine at position 61 was the only residue where no substitution was tolerated. Analogue peptides that did not induce CTL-mediated lysis were tested as competitors with the natural peptide; those with substitutions at positions 60, 64, and 65 inhibited, identifying residues that interact with the TCR. Another approach was to test a set of four CTL clones on all of the analogues. Marked differences in recognition by individual CTL clones were observed for several substituted peptides. The data indicate that most of the analogues bind to HLA-A2 with possible differences in fine positioning of the peptide. An alpha helical orientation for the peptide is discussed.


Virology ◽  
2009 ◽  
Vol 384 (1) ◽  
pp. 28-32 ◽  
Author(s):  
Shufang Fan ◽  
Guohua Deng ◽  
Jiasheng Song ◽  
Guobin Tian ◽  
Yongbing Suo ◽  
...  

2009 ◽  
Vol 83 (19) ◽  
pp. 9875-9889 ◽  
Author(s):  
Elodie Beaumont ◽  
Daniela Vendrame ◽  
Bernard Verrier ◽  
Emmanuelle Roch ◽  
François Biron ◽  
...  

ABSTRACT Lentiviruses, including human immunodeficiency virus type 1 (HIV-1), typically encode envelope glycoproteins (Env) with long cytoplasmic tails (CTs). The strong conservation of CT length in primary isolates of HIV-1 suggests that this factor plays a key role in viral replication and persistence in infected patients. However, we report here the emergence and dominance of a primary HIV-1 variant carrying a natural 20-amino-acid truncation of the CT in vivo. We demonstrated that this truncation was deleterious for viral replication in cell culture. We then identified a compensatory amino acid substitution in the matrix protein that reversed the negative effects of CT truncation. The loss or rescue of infectivity depended on the level of Env incorporation into virus particles. Interestingly, we found that a virus mutant with defective Env incorporation was able to spread by cell-to-cell transfer. The effects on viral infectivity of compensation between the CT and the matrix protein have been suggested by in vitro studies based on T-cell laboratory-adapted virus mutants, but we provide here the first demonstration of the natural occurrence of similar mechanisms in an infected patient. Our findings provide insight into the potential of HIV-1 to evolve in vivo and its ability to overcome major structural alterations.


Sign in / Sign up

Export Citation Format

Share Document