PEPTIDOS SINTETICOS E SUAS MISTURAS PARA A DETECCAO DE ANTICORPOS HIV

There is provided cyclic peptides of the general formulae: (I) (III) wherein x represents an amino acid sequence from position 585 to 604 (gp41-HIV-1) such amino acid sequences being characterized by at least one of a lysine at position 586 or a lysine at both positions 585 and 586; x2 represents an amino acid sequence from position 585 to 604 (gp41-HIV-1); y represents an amino acid sequence from position 612 to 629 (gp41-HIV-1); e and f represent one or more epitopes; and a and b represent the amino and carboxy terminals, respectively, as well as substituents which are effective to make the peptide more useful as an immunodiagnositc reagent. Peptides of formula III have one or both of e and f present. There is also provided peptides of the general formulae: (II) (IV) wherein x1 represents an amino acid sequence from position 577 to 596 (gp36-HIV-2) such amino acid sequences being characterized by at least one of a lysine at position 578 or a lysine at both positions 577 and 578; x3 represents an amino acid sequence from position 577 to 596 (gp36-HIV-2); y1 represents an amino acid sequence from position 604 to 613 (gp36-HIV-2); e and f represents one or more epitopes; and a and b are as defined above. Peptides of formula IV have one or both of e and f present. These cyclic peptides alone or in admixture with other peptides are particularly useful in detecting HIV-1 and HIV-2 antibodies in analytes and sera.