Abstract: The present invention pertains to a molecular biology-based method and kit for measuring the specific growth rate (or cell doubling time) of distinct microbial populations. The method and kit can be used to analyze mixed culture samples that have been exposed to chloramphenicol or other protein synthesis inhibitors for defined times. In a preferred embodiment, the method of the invention (also referred to herein as FISH-RiboSyn) is an in situ method that utilizes fluorescence in situ hybridization (FISH) with probes that target: (1) the 5? or 3? end of precursor 16S rRNA; or (2) the interior region of both precursor 16S rRNA and mature 16S rRNA. Images can be captured for a defined exposure time and the average fluorescent intensity for individual cells can be determined. The rate of increase of the whole cell fluorescent intensity is used to determine the specific growth rate.

Abstract: The subject invention concerns materials and methods for evaluating the susceptibility of bacterial cells to an antibiotic or other antimicrobial compound or agent. In one embodiment, a sample comprising a microbial population is exposed to an antibiotic of interest. The sample is then processed using FISH-RiboSyn methods to determine the specific growth rate of the antibiotic-exposed microbes as compared to an untreated control. The subject invention also concerns materials and methods for determining the most suitable and/or effective antibacterial treatment for a person or animal having a bacterial infection.

Abstract: The present invention pertains to a molecular biology-based method and kit for measuring the specific growth rate (or cell doubling time) of distinct microbial populations. The method and kit can be used to analyze mixed culture samples that have been exposed to chloramphenicol or other protein synthesis inhibitors for defined times. In a preferred embodiment, the method of the invention (also referred to herein as FISH-RiboSyn) is an in situ method that utilizes fluorescence in situ hybridization (FISH) with probes that target: (1) the 5? or 3? end of precursor 16S rRNA; or (2) the interior region of both precursor 16S rRNA and mature 16S rRNA. Images can be captured for a defined exposure time and the average fluorescent intensity for individual cells can be determined. The rate of increase of the whole cell fluorescent intensity is used to determine the specific growth rate.