Acid stress upregulated outer membrane proteins in clinical isolates of Neisseria gonorrhoeae, but not most commensal Neisseria

Human immune serum recognition of outer membrane components from commensal and pathogenic Neisseria cultured under neutral and acidic conditions was i nvestigated. Acid stress caused no detectable alterations in lipooligosacch aride migration and (or) staining, in outer membrane protein profiles, or i n immune serum recognition of outer membrane components from Neisseria muco sa or Neisseria sicca. There was also no difference in the lipoologosacchar ide electrophoretic pattern of acid- and neutral-grown Neisseria lactamica, but there were differences in outer membrane protein expression. The outer membrane protein alterations induced by acid stress in N. lactamica were n ot the same as those seen in isolates from patients with uncomplicated gono coccal infection, pelvic inflammatory disease, and disseminated gonococcal infection. Many differences were detected in the immune serum recognition o f outer membrane components from acid- and neutral-cultured N. lactamica an d from the clinical isolates of Neisseria gonorrhoeae, and these should be considered in vaccine design.