NEET PG Medical – 2020 – Question – 93
Which of the following cell components produced by Neisseria gonorrhoeae is responsible for attachment to host cells?
a) Lipooligosaccharide
b) Pili (fimbriae)
c) IgA1 protease
d) Outer membrane porin protein
Correct Answer – B
Answer- B- Pili (fimbriae)
Pili are hair-like appendages that extend up to several micrometers from the gonococcal surface. They enhance attachment to host cells and resistance to phagocytosis. They are made up of stacked pilin proteins.
The amino terminal of the pilin molecule, which contains a high percentage of hydrophobic amino acids, is conserved. The amino acid sequence near the midportion of the molecule also is conserved; this portion of the molecule serves in an attachment to host cells and is less prominent in the immune response.
The amino acid sequence near the carboxyl-terminal is highly variable; this portion of the molecule is most prominent in the immune response. The pilins of almost all strains of N. gonorrhea are antigenically different, and a single strain can make many antigenically distinct forms of pilin.
Jawetz 27/e-pg-282
