Dr. Jerse has worked in the area of bacterial pathogenesis for over 30 years and on Neisseria gonorrhoeae since 1991 with a focus on gonococcal adaptation to the genital tract using human and murine infection models. Her laboratory is also very active in the development of vaccines, vaginal microbicides and novel anti-infectives, which are needed to combat the serious problem of antibiotic resistance in N. gonorrhoeae. To better understand the spread of antibiotic resistance in the gonococcus, Dr. Jerse studies the relationship between antibiotic resistance genes and gonococcal fitness in vitro and in vivo. In this presentation she will discuss how some antibiotic resistance alleles (i.e. mtr mutations, gyrA mutations, mosaic penA alleles) confer a fitness benefit or cost to the gonococcus and how compensatory evolution can rescue fitness disadvantages that accompany some resistance mutations. This line of investigation helps elucidate the spread of antibiotic resistant strains and may explain why resistant strains can be maintained within communities in the absence of antibiotic pressure.