14 topics with concise breakdowns: definitions, key facts, and class questions.
Welcome to the Microbial Genetics section. Here we examine how bacteria and viruses store, alter, and transmit their hereditary information. You will learn why microorganisms acquire antibiotic resistance so quickly and what role plasmids and mobile genetic elements play in this process.
The section covers key genetic processes: from mutations and DNA repair systems to horizontal gene transfer. We examine in detail the classic trio of mechanisms for genetic information transfer in bacteria: conjugation, transduction, and transformation. A dedicated article covers the specifics of viral genetics.
In practical classes and exams, you will certainly be asked how this knowledge is applied in practice. Therefore, in the second part of the section, we thoroughly examine modern methods of molecular genetic analysis: PCR, restriction analysis, molecular hybridization, and ribotyping. This is an absolute baseline for understanding modern laboratory diagnostics of infections.
This is a discrete segment of DNA with a unique nucleotide sequence that encodes a specific protein.
What is the difference between an episome and a regular plasmid?
An episome is a plasmid capable of reversible integration. It can reside autonomously in the cytoplasm or integrate into the bacterial chromosome and replicate along with it as a single replicon.
Are mobile elements capable of autonomous replication?
No, they are not independent replicons. Their replication occurs passively, exclusively during the duplication of the DNA molecule into which they are integrated.
What is a transition?
This is a type of point mutation in which a purine base is replaced by another purine (or a pyrimidine by a pyrimidine). It occurs, for example, under the action of base analogs.
Does dark repair depend on the presence of light?
No, dark (excision) repair proceeds independently of light, whereas light repair (photoreactivation) requires the obligatory presence of light to activate the enzyme.
What is a merozygote in microbiology?
This is an incomplete, partially diploid cell formed after only a fragment of donor DNA, rather than an entire chromosome, penetrates the recipient bacterium.
Study the full topic in the «Microbiology» course
This is a summary. The course covers everything tested in classes and exams.
4,383 pages of study guides across all topics
Assignments and quizzes after every topic — just like in a colloquium