uspA1 of Moraxella catarrhalis clinical isolates in Japan and its relationship with adherence to HEp-2 cells.
The surface protein, UspA1, of Moraxella catarrhalis is involved in adherence to human epithelial cells. We examined the expression of uspA1, and adherence to HEp-2 cells of clinical isolates. The uspA1 gene was detected in 204 of 208 isolates. The 4 uspA1-negative isolates belonged to the 16S rRNA type II with an A to G substitution at nucleotide 445 of 16S rRNA. In 13 isolates of the 16S rRNA type II, transcription of uspA1 was decreased or absent. A relationship between the extent of uspA1 transcription and adherence to HEp-2 cells was found in 5 isolates of the type I. In contrast, the 16S rRNA type II strains still had considerable adherence to HEp-2 cells. The type I uspA1 gene was expressed in Escherichia coli JM109 and the transformants adhered to HEp-2 cells at rates about 7 times higher than the host strain. These data indicated that the uspA1 was virtually ubiquitous in clinical isolates of M. catarrhalis and was responsible for adherence to HEp-2 cells of 16S rRNA type I isolates. However, the data also suggested that adherence of 16S rRNA type II strains to HEp-2 cells was attributed to factor(s) other than UspA1.
Qiu
Hongli
H
Department of Microbiology and Immunology, Graduate School of Health Sciences, Tokyo Medical and Dental University, Yushima, Bunkyo-ku, Tokyo. qiuhl2004@yahoo.co.jp
Kumita
Wakako
W
Sato
Kenya
K
Nakajima
Shinichi
S
Nishiyama
Hiroyuki
H
Saito
Ryoichi
R
Sawabe
Etsuko
E
Ono
Emi
E
Chida
Toshio
T
Okamura
Noboru
N
D018829:Adhesins, Bacterial / Q000235:genetics / Q000502:physiology*; D001422:Bacterial Adhesion / Q000502:physiology*; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000502:physiology*; D015373:Bacterial Typing Techniques; D003001:Cloning, Molecular; D004847:Epithelial Cells / Q000502:physiology; D006801:Humans; D001936:Moraxella catarrhalis / Q000737:chemistry*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
D018829:Adhesins, Bacterial; D001425:Bacterial Outer Membrane Proteins; D012336:RNA, Ribosomal, 16S; C089675:UspA protein, Moraxella catarrhalis