Entamoeba histolytica: cDNAs cloned as 30kDa collagen-binding proteins (CBP) belong to an antioxidant molecule family. Protection of hamsters from amoebic liver abscess by immunization with recombinant CBP.
A cDNA expression library of Entamoeba histolytica was screened with antiserum to native amoebic collagen binding proteins (CBPs), and two clones C13 and C7 which partially encode for the 30 kDa CBP were obtained. The sequenced clones were 90% homologous. C7 had a 69 bp deletion at the 5' end that is present in C13 and encodes for a Glu-Cys-Lys rich region and a four amino acids repeat (Glu-Lys-Glu-Cys). Purified fusion proteins from these cDNA clones were able to bind native type I collagen gels in a pH, calcium, ionic strength, and temperature dependent way. The binding of pgtC13 to collagen gel was time and temperature stable, while pgtC7 binding was not, suggesting that the deleted region in C7 is important for the binding. The clones reported here partially encode a 30 kDa CBP that also belong to an antioxidant molecule family. We demonstrated that the fusion protein pgtC13 is immunogenic and partially protective as a subunit vaccine in the hamster model of amoebic liver abscess.
Jiménez-Delgadillo
Bertha
B
Departamento de Patología Experimental, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, México City, D.F. CP 07360, Mexico.
Chaudhuri
Partha P
PP
Baylón-Pacheco
Lidia
L
López-Monteon
Aracely
A
Talamás-Rohana
Patricia
P
Rosales-Encina
José Luis
JL
D000595:Amino Acid Sequence; D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000378:metabolism; D001483:Base Sequence; D015153:Blotting, Western; D003001:Cloning, Molecular; D003094:Collagen / Q000378:metabolism; D016384:Consensus Sequence; D006224:Cricetinae; D018076:DNA, Complementary / Q000737:chemistry* / Q000302:isolation & purification; D016054:DNA, Protozoan / Q000737:chemistry / Q000302:isolation & purification; D004195:Disease Models, Animal; D004591:Electrophoresis, Polyacrylamide Gel; D004748:Entamoeba histolytica / Q000235:genetics* / Q000276:immunology; D008101:Liver Abscess, Amebic / Q000517:prevention & control*; D008297:Male; D008647:Mesocricetus; D008969:Molecular Sequence Data; D010957:Plasmids / Q000737:chemistry / Q000235:genetics; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D016052:Protozoan Vaccines; D016415:Sequence Alignment; D022223:Vaccines, Subunit
D000975:Antioxidants; D018076:DNA, Complementary; D016054:DNA, Protozoan; D015800:Protozoan Proteins; D016052:Protozoan Vaccines; D022223:Vaccines, Subunit; D003094:Collagen