by Elio — Broadly speak­ing, fit­ness in mi­cro­bi­ol­ogy is the abil­ity of mi­crobes to thrive in a com­pet­i­tive en­vi­ron­ment. It is of­ten de­ter­mined by com­par­ing the growth rate in a given en­vi­ron­ment of a mu­tant strain with that of its non-mu­tant iso­genic rel­a­tive. If the mu­tant is less fit, it will grow more slowly...