Competition between Neisseria gonorrhoeae and Staphylococcus epidermidis during iron-limited or replete continuous culture.
Neisseria gonorrhoeae strain P9-2 was grown in iron-limited or replete continuous culture at a dilution rate of 0.05 h-1, in the presence and absence of Staphylococcus epidermidis. Gonococci maintained expression of pili (P+) and the transparent colony phenotype in pure culture during transitions of iron- and cystine-limited growth. They competed well with staphylococci during iron-limited co-culture and comprised greater than 95% of the population. Transition to cystine-limited growth allowed the staphylococcus to predominate but the gonococcus did not wash out. Furthermore, the gonococcal opaque colony phenotype (O+), indicating synthesis of outer membrane proteins II, was now expressed. Restoration of iron limitation returned the co-culture to its original composition but with P+O+ gonococci dominating. These results suggest that environments might exist in Man where gonococci can compete successfully with normal indigenous bacteria during infection.
Keevil
C W
CW
Pathogenic Microbes Research Laboratory, PHLS Centre for Applied Microbiology and Research, Salisbury, U.K.
Spillane
B J
BJ
D007501:Iron / Q000378:metabolism*; D009344:Neisseria gonorrhoeae / Q000254:growth & development*; D010641:Phenotype; D013212:Staphylococcus epidermidis / Q000254:growth & development*
D007501:Iron