부산대학교 도서관

ABSTRACTAdhesion to the respiratory epithelium plays an important role in Haemophilus influenzaeinfection. The distribution of H. influenzaeadhesins in type b and nontypeable strains has been characterized, but little is known about the prevalence of these factors in non-type b encapsulated strains. We analyzed 53 invasive type a, type e, and type f strains for the presence of hap, hia, hmw, and hifgenes; Hap, Hia, and HMW1/2 adhesins; and hemagglutinating pili. The hapgene was ubiquitous, and homologs of hmwand hiawere present in 7 of 53 (13.2%) and 45 of 53 (84.9%) strains, respectively. Hap was detected in 28 of 45 (62.2%) hap+strains, HMW1/2 was detected in 5 of 7 (71.4%) hmw+strains, and Hia was detected in 31 of 45 (68.8%) hia+strains. The hifgene cluster was present in 26 of 53 strains (49.1%), and 21 of 26 hif+strains (80.8%) agglutinated (HA) red blood cells. Nine isolates exhibited HA but lacked the hifgene cluster. The distribution of adhesin genes correlated with the genetic relatedness of the strains. Strains belonging to one type a clonotype and the major type e clonotype possessed hiabut lacked the hifcluster. Strains belonging to the second type a clonotype possessed both hiaand hifgenes. All type f strains belonging to the major type f clonotype possessed hiaand lacked hifB. Although the specific complement of adhesin genes in non-type b encapsulated H. influenzaevaries, most invasive strains express Hap and Hia, suggesting these adhesins may be especially important to the virulence of these organisms.