Author/Editor		Drobnič-Valič, Magda
Title		Molekularne osnove nastanka antigenskih variant hemaglutinina pri bakteriji Mycoplasma synoviae
Translated title		Molecular basis of Mycoplasma synoviae hemagglutinin antigenic variants
Type		monografija
Place		Ljubljana
Publisher		Medicinska fakulteta
Publication year		2001
Volume		str. 108
Language		slo
Abstract		Mycoplcasma synoviae (MS) synthesizes variant forms of hemagglutinins (VLHA), immunodominant membrane lipoproteins which seem to be associated with pathogenicity. Variant forms of VLHA are encoded by a single expressed vlhA gene and numerous pseudogenes that can recombine with the expressed vlhA. The relationship between molecular changes of VLHA proteins generating antigenic variants and changes in the HA phenotype and MS infectivity is not well understood. In the majority of MS strains VLHA proteins can be cleaved into the N-terminal part, lipoprotein MSPB and the C-terminal part MSPA, which mediates binding to erythrocytes. In this study sequence analyses of the 5'-end of the vlhA gene of 23 MS strains revealed a considerable sequence diversity, particularly within the part encoding the proline-rich region (PRR) at the N-terminus of the MSPB protein. The most pathogenic strain K1968 contained in the PRR an insertion of seven amino acids (DNPQNPN). All other strains examined had deletions (615 amino acids) in the PRR, whereas strains F10 2AS, K2581, K3344 and a cluster of five related strains ULB001 lacked the second repeat of 19 amino acids. Differences in the PRR were correlated with the lengths of the corresponding MSPB proteins detected in immunoblots with specific antibodies. Comparison of the sequences within the 5'-end vlhA of different MS strains indicated that sequence analyses could be used for strain differentiation and for epizootiological studies of MS infections. Comparison of the predicted MSPB sequences of MS isogenic lineages differing in the hemagglutination (HA) phenotype and expressing distinct MSPB antigenic variants deimed by monoclonal antibodies (mAbs 50, 125, 3A8 and 3B4), revealed the first hemagglutinin variable domain (HVD 1) associated with distinct antigenic variants and eventually with changes in the HA phenotype. (Abstract tuncated at 2000 characters)
Descriptors		MYCOPLASMA IMMUNODOMINANT EPITOPES POLYMORPHISM (GENETICS) HEMAGGLUTININS GENOME, BACTERIAL POLYMERASE CHAIN REACTION BASE SEQUENCE TRANSFORMATION, GENETIC