ABSTRACT
One of the most difficult problems in medicine today is antibiotic resistance. Pathogenic microorganisms can become resistant to antibiotics through mutation, a process that causes changes in the genetic information of the organisms. These changes can be transferred from one organism to another, which means that microbes have the capacity to take up genetic information, exchange it, and develop it further. The genetic changes resulting from these exchanges can make harmless organisms dangerous (pathogenic) and pathogenic organisms lethal (more virulent). To understand pathogenesis and virulence, we must be familiar with microbial genetics. In this chapter, we begin to acquire this familiarity by looking at the structure of the nucleic acids DNA and RNA. We then examine the processes of replication, gene expression, mutation, and gene transfer and end the chapter by taking a look at the genetics of pathogenesis and virulence.
