Neisseria meningitidis NaIP

• What is NaIP?

  This is a surface exposed auto transporter found in Neisseria meningitidis. It exhibits serine protease activity and can cleave several proteins on the outer membrane of Nm.
• Describe the role of NaIP in Nm immune evasion

  NaIP can cleave human C3, which occurs 4 aa upstream from the natural cleave site to produce a shorter C3a-like fragment and longer C3b-like fragment. The C3a-like fragment lacks the C-terminal arginine, which is known to be essential for its anaphylatoxin activity. Furthermore, C3b-like fragment is susceptible to degradation by the complement inhibitors, factor-H and factor-I. This results in reduced deposition of C3b on the surface of Nm.