Microbial Genetics and Molecular Biology - BST 325

These flashcards cover key concepts and methodologies in microbial genetics, focusing on genetic recombination, mutation, DNA repair mechanisms, and applications in biotechnology.

What is genetic recombination in prokaryotes and what are its main strategies?

Genetic recombination is the exchange of genetic material between different organisms in prokaryotes, primarily through transformation, transduction, and conjugation.

What role does Gregor Mendel play in genetics?

Gregor Mendel is known as the pioneer of genetics for his work on trait inheritance and the principles of segregation and independent assortment.

What are the key differences between sexual reproduction in eukaryotes and asexual reproduction in prokaryotes?

Eukaryotic sexual reproduction involves genetic recombination and variation via meiosis, while prokaryotic asexual reproduction, such as binary fission, produces genetically identical clones with minimal variation.

Explain the process of transformation in bacteria.

Transformation is the uptake of extracellular DNA by a competent bacterial cell, which can then recombine with the bacterial genome, imparting new traits.

Describe transduction in the context of bacterial genetics.

Transduction is a method of genetic exchange where bacteriophages carry bacterial genes from one cell to another, which can occur via the lytic or lysogenic cycles.

What is conjugation in prokaryotes?

Conjugation is the transfer of DNA between two bacterial cells through direct physical contact, often facilitated by a structure called a pilus.

Define phage conversion and its significance.

Phage conversion (lysogenic conversion) occurs when a temperate bacteriophage integrates its DNA into the host's genome, potentially conferring new pathogenic properties to the host.

What are plasmids, and why are they important in microbial genetics?

Plasmids are small, circular DNA molecules found in bacteria, which carry genes that can provide advantages such as antibiotic resistance and can be transferred between organisms.

What is the significance of nitrogen-fixing bacteria?

Nitrogen-fixing bacteria convert atmospheric nitrogen into ammonia, which is essential for plant nutrition and can significantly impact agricultural practices.

What are the main steps involved in Base Excision Repair (BER)?

The steps in BER include recognition of damaged bases, removal of the damaged base, single-strand break creation, gap filling by DNA polymerase, and sealing the nick by DNA ligase.

What is the difference between point mutations and large-scale mutations?

Point mutations involve changes to one or a few nucleotides, while large-scale mutations affect larger segments of DNA, including entire genes or chromosomal alterations.

What are the consequences of mutations within DNA?

Mutations can be beneficial, neutral, or harmful, leading to genetic diversity, disease, or adaptations in populations.

How do DNA repair mechanisms help maintain genomic integrity?

DNA repair mechanisms correct damaged DNA, preventing mutations and maintaining stability, which is crucial for preventing genetic disorders and cancer.

Explain the role of bacteriophage genetics in biotechnology.

Bacteriophage genetics can be exploited for applications in gene delivery, bacterial identification, and therapeutic uses against bacterial infections.

Differentiate between lytic and lysogenic cycles of bacteriophages.

The lytic cycle results in the destruction of the host cell and release of new phages, while the lysogenic cycle allows the phage DNA to incorporate into the host genome without killing it, replicating with the host cell.

What is the Central Dogma of molecular biology?

The Central Dogma refers to the flow of genetic information from DNA to RNA to protein, governing how genes are expressed in living organisms.

What methods are used for bacterial identification in microbial genetics?

Methods include DNA sequencing, PCR, and genotypic techniques like pulsed field gel electrophoresis and molecular subtyping.