T4-lymphocyte endoprotease responsible for the proteolytic processing of HIV-1 gp160, like Kex2p endoprotease, is a calcium-dependent enzyme.
In the present study we show that precursor gp160 is cleaved in the HIV-1 infected CEM (CD4+) cell line preferentially in the presence of calcium ions demonstrating that the responsible cellular endoprotease is a calcium-dependent enzyme. Taking into account this similarity, a synthetic peptide modelling the cleavage site of HIV-1 envelope glycoprotein precursor was used as substrate for Kex2p. Results obtained clearly showed that the processing enzyme Kex2p (EC 3.4.21.61), a subtilisin-like serine protease that is encoded by the KEX2 gene of yeast Saccharomyces cerevisiae is able to cleave correctly this peptide at the potential cleavage site.
Moulard
M
M
Institut für Virologie, Klinikum der Philipps-Universität Marburg, Germany.
Achstetter
T
T
Ikehara
Y
Y
Bahraoui
E
E
D000595:Amino Acid Sequence; D001345:Autoradiography; D015496:CD4-Positive T-Lymphocytes / Q000201:enzymology*; D000001:Calcimycin / Q000494:pharmacology*; D002118:Calcium / Q000502:physiology*; D002460:Cell Line; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D015686:Gene Products, env / Q000302:isolation & purification / Q000378:metabolism*; D019302:HIV Envelope Protein gp160; D015497:HIV-1 / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D008715:Methionine / Q000378:metabolism; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis / Q000378:metabolism; D043484:Proprotein Convertases; D011498:Protein Precursors / Q000302:isolation & purification / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins; D013379:Substrate Specificity; D013381:Subtilisins / Q000235:genetics / Q000378:metabolism*
D015686:Gene Products, env; D019302:HIV Envelope Protein gp160; D010455:Peptides; D011498:Protein Precursors; D029701:Saccharomyces cerevisiae Proteins; D000001:Calcimycin; D008715:Methionine; D043484:Proprotein Convertases; D013381:Subtilisins; C058751:KEX2 protein, S cerevisiae; D002118:Calcium