Special cell types and gene transfer Flashcards
Magnetoglobus multicellularis
A group of 10-40 cells that have about 80 bullet shaped magnetosomes that take up metal particles and gives the cell a sense of location
Clostridium difficile
Example of opportunistic infection, it takes over gut and is a recurring infection, common in hospitals
Vegetative
metabolically active
Akinetes
Cyanobacteria, dormant, have thick cell walls filled with food reserves
What type of photosynthesis do cyanobacteria perform?
oxygenic
Heterocysts
Produced by some cyanobacteria that can fix N, anearobic, maintained by 3 layered cell wall and degradation of photosystem II proteins because O2 inhibits N fixation
Conjugation
copying and transmission of a plasmid
Transformation
cell acquires DNA from its environment and the DNA is released when the cell dies. That DNA can then be incorporated into another cell
pGlo lab
Cell is damage to get DNA into cells then selectable marker is introduced to only survival of those that picked up DNA
Acinetobacter baumanii
Forms biofilms on organic and inorganic surface, picks up DNA from many sources, toxic, antibiotic R GENES
Transduction
Virus infects bacteria with phagesand replication begins there, DNA from host becomes part of viral particle, virus infects another cell and new host cell incorporates DNA from previous host cell into genome
Robert Koch
Developed and organized method for demonstrating the link between microbe and illness with postulates
- Observe microorganism in all cases of disease, not usually seen in healthy organisms
- Isolate pure culture of microbe
- Observe disease characteristics in test subjects
- Isolate same microbe from test subjects
Tobacco mosaic virus significane
1st isolated virus
Living and nonliving components of viruses
Nonliving: cell membrane, no growth or metabolism, different from living parasites bc viruses require a host to replicate, parasites replicate themselves
Living: Replication, evolution, genetic material
Genome of a virus
DNA and RNA
Capsid
protein coat around virus consisting of capsomeres
Viral envelope
Present with some viruses, have spikes, help with attachment
Roles of viruses in terms of population
limit host cell density(population control)
Where can the 16s RNA gene be found in eukaryotes? what is its significance?
Mitochondria genome, most closely related to 16s bacteria
Theory of Endosymbiosis
A theory proposing the origin of eukaryotic cells, proposed by Lynn Margulies, a larger cell engulfs a smaller prokaryotic cell or the smaller cell invades through phagocytosis. A mutual relationship was established and the smaller cell became an organelle over time
Molecular evidence supporting theory of endosymbiosis
Genomes of mitochondria and chloroplast: circular chromosomes, order of genes are similar to bacteria, gene processing is similar to bacteria
Mito and chloro ribosomes: Similar size as bacterial ribosomes, they process proteins more like bacteria than eukaryotes
Structural evidence supporting theory of endosymbiosis
Mitochondria and chloroplasts are made through division and have double membranes
Extant evidence supporting the theory of endosymbiosis
- Sea slug that sucks up algae and imports chloroplasts into digestive system
- Cell that eats algae, and moves toward light when algae are present and feeds them with carbon if not present
- Protist that switches from predator to producer if it eats algae, feeding tube disappears and is replaced with plastid. Algal cell loses most organelles
- Glaucophytes have 2 membranes and thin layer of peptidoglycan
Primary endosymbiosis
Prokaryote is engulfed resulting in 2 membranes
