mm pp 6 Flashcards
Fastidious Organisms
Very Hard to grow in lab culture due to high requirements
Minimum requirements for Growth of microbe
Carbon Source, Nitrogen Source, Energy Source, Water, Ions
Autotrophs
Need CO2
Heterotrophs
Need Organic Carbons
Major Essential Elements
Carbon, Oxygen, Hydrogen, Nitrogen, Iron, Sulfur, etc
Some bacteria require _____ and _____ to be oxidized for ATP
Iron and Sulfur
Some bacteria require minor elements to act as ________ for enzymes
Cofactors
Obligate Aerobes
Must have oxygen to survive
Obligate anaerobe
Cannot have oxygen due to buildup of toxic radical oxygen compounds
Facultative Anaerobes
Can have air, or not. Either is fine.
Catabolism
Breakdown of large molecules to smaller molecules for metabolism
Anabolism
Build small molecules up to larger ones. Need energy to do so.
Oxidative Phosphorylation
Need electron transport chains to allow for aerobic respiration
Substrate level phosphorylation
The internal change of ADP to ATP by moving phosphate compounds around
Anaerobic Respiration
Use of non-oxygen compounds to form energy. Fe+2 can be used as an electron acceptor
Most pathogenic microbes need _________
Sugar, proteins and fats
Some Pathogenic microbes need _________
ONly inorganic nutrients and a Carbon source while others have extensive frowth requirements
Some microbes are difficult or impossible to grow __________
in vitro
Glycolysis yields
2 atp, 2 NADH+ H+, and 2 pyruvate
Fermentation requires ______ and ________ to be used
NADH and Pyruvate
The citrate cycle or Krebs cycle yields
2 CO2, 3 NADH, 1 FADH2, and 1GTP
Citrate cycle is a _________ pathway
Amphibolic
Oxidative Phosphorylation of NADH yields __________
3 ATP
Oxidative Phosphorylation of FADH2 yields _________
2 ATP
About _______ ATP can be generated from glucose
38
Oxygen is the major electron acceptor of _________
Oxidative Phosphorylation
NO3-, SO4-2, CO2 can be _________ in some bacteria
Electron Acceptors
RNA Synthesis is called ________ and DNA is the template
Transcription
Protein synthesis is called ________ and mRNA is the template
Translation
DNA synthesis is called _______ and DNA is the template
Replication
RNA dependent RNA polymerase
Transcriptase
RNA-Dependent DNA polymerase
Reverse Transcriptase
Transcription requirements
DNA template, RNA polymerase with sigma factor (dont have to have but increases efficiency)
Polycistronic
Codes for more than one peptide
Operons
Cluster of genes that contain a promoter and more than one protein gene that is transcribed as a unit (all of none made)
Inducible Operons-
Must be activated by inducers like Lactose operon
Repressible operons
Transcribed continually until deactivated by repressers like Tryptophan Operon
mRNA contains sequences of codons that code for _________ in a peptide
Amino Acids
AUG is the ________ codon
Start
Peptidyl Transferase-
Forms peptide bond
Translocase-
Moves to next codon
Translation occurs at _____ Amino Acids/sec
40
Translation occurs from _________ direction
5’ to 3’
Proteins are made as soon as ribosomes bind ________
5’ end of mRNA
Quorom Sensing-
Biofilm communication method that is mediated through Agr proteins.
DNA replication is ________
Semiconservative
DNA replication requires-
Topoisomerases, Helicase, DNA binding proteins, primosome or primase, DNA polymerase III, DNA polymerase I, and DNA ligase
DNA replication requires around _________ minutes to complete
40
Once DNA synthesis is initiated it is completed even if ________
Nutrients are depleted
Helicase-
Breaks the DNA apart
Primase-
Primes the DNA to synthesize RNA at 5’ end
DNA polymerase III and I
Primary DNA pilymerase that adds on nucleotides
Topoisomerases-
Precede the replication fork and unwind the DNA to relax tension
Replication occurs at the ________
Replication fork
origin of replication-
Where the Replication process begins
Bacterial DNA replication is __________
Bidirectional (occur at both the leading and lagging strand)
Lag phase of bacterial growth-
Adapting to the medium
Exponential or Log Phase of Bacterial Growth
Cells dividing at constant rate. 2^n where n is the number of generations. (Approx. 30 minute generation times)
Stationary phase of bacterial growth
Low nutrients or oxygen or increase in toxin. Plateau in graph
Decline phase of bacterial growth
Death and Lysis, some cells may survive
Bacterial cell growth can be measured in fluid by ________
Optical density measurements of turbidity
Substitution Mutations- Transitions
(pur->pur or Pyr->pyr)
Substitution Mutations- Transversions
(pur->pyr or pyr->pur)
Silent Mutation-
No change in amino acid
Missense and conservative point mutations-
Change 1 amino acid and protein is still functional. Does effect ability of protein
Nonsense Mutation-
Stop Codon
Frameshift Mutation-
Insertion or deletion . VERY SEVERE!
Null or lethal mutation-
Non-functional Protein
Spontaneous mutation-
Polymerase mistakes
Mutagens and Nucleotide analogs-
Substitution of nucleotides
Direct DNA repair-
T-T or altered base repair such as with photolyase
Excision Repair-
Segment removed and replaced
Post replication repair-
Recombination when both strands are damaged. Rare.
SOS response-
15 genes induced
Error prone repair-
Rapid effort to replace damaged sequences with random pieces of DNA before cell dies
Transformation-
Released dsDNA or plasmids taken up by bacteria
Transduction-
Use of bacteriophages to inject genetic sequences into bacterial genome
Transformation is natural in ________
B. Subtilis, H. Influenza, N. gonorrhea, S. pneumoniae
Chemicals and electricity can enhance _______
Transformation
_________ transfer the DNA into the bacteria in transformation
Plasmid
Plasmids can carry _________
Abx resistance genes, Toxin genes, enzymes, etc
Plasmids are self-_______
Replicating
Conjugation-
Sexual genetic transfer by use of a sex pilus and F plasmid
Transposition
Have transposable elements called transposons that are mobile within the cell. These transfer one DNA molecule to another such as nucleoid to plasmid, plasmid to nucleoid, etc
F factor codes for ______
Fertility factor
Hfr-
High frequency recombination
Pathogenicity Islands-
Transposons with virulence genes
Transposons contain-
A central-region coding for resistance or toxin flanked by two insertion sequences for the genomic DNA
Competant Cells-
Have been treated to take up plasmids very readily. Treated with salts usually