1 LEC: Bacterial Morphology, Genetics, Cultivation and ID Flashcards
genetic potential of the organism’s DNA
genotype
expressed genetic characteristics
phenotype
prokaryotic transcription occurs in the ___ alongside translation
cytoplasm
single dsDNA, closed, circular, and supercoiled bacterial chromosome
bacterial genome
extrachromosomal dsDNA; not essential for growth
plasmids
jumping genes
transposons
mobile, can jump from one place in the chromosome to another
transposons
jumping genes can either be ___ or ___
simple or composite
simplest mobile piece of DNA
insertion sequence element
causes disruption and inactivation of gene
insertion sequence element
significant in antibiotic resistance
plasmids
transposons
gene transfer/exchange between homologous regions on 2 DNA molecules
genetic recombination
Mechanisms of gene transfer:
take up of naked DNA into bacterial cell
transformation
species that undergo transformation
S. pneumoniae, N. gonorrhoeae, H. influenzae
Mechanisms of gene transfer:
transfer of genes by a bacteriophage
transduction
species that undergo transduction
C. diphtheriae
refers to the phage in lysogeny
temperate
Mechanisms of gene transfer:
transfer of genetic material from a donor to a recipient strain
sex pili/conjugation pili
changes in the base sequence of DNA
mutations
insertion of different amino acids leading to a different phenotype
mutations
mutation:
due to tautomeric shift of electrons in bases
spontaneous
mutation:
due to mutagens
induced
bacteria that use CO2 as source of carbon
autotroph
bacteria that require complex substances for growth
heterotroph
Identify:
Energy source: light
Carbon source: CO2
photoautotroph
Identify:
Energy source: light
Carbon source: organic compounds
photoheterotroph
Identify:
Energy source: organic compounds
Carbon source: CO2
chemoautotroph
Identify:
Energy source: organic compounds
Carbon source: organic compounds
chemoheterotroph
growth requirement:
synthesis of cell component
carbon source
growth requirement:
for protein synthesis
nitrogen source
metals needed by bacteria as growth requirement
Mg, K, Fe, Cl, Na, Ca
Bacteria that require high osmotic pressure are called ___
archaeabacteria (osmophilic)
additional requirement:
Haemophilus spp.
blood (X and V factors)
additional requirement:
Mycobacterium spp.
protein
additional requirement:
Vibrio spp.
salt
additional requirement:
Legionella pneumophila
cysteine
optimum pH for bacterial growth
6.5-7.5
Acidophilic bacterial species
Lactobacillus acidophilus
Alkaphilic bacterial species
Vibrio cholerae
Optimum temperature:
mesophilic
20-40C
Optimum temperature:
thermophilic
50-60C
Optimum temperature:
psychrophilic
<20C
Optimum temperature:
bacteria with short optimum temperature range are called
sternothermophilic
Optimum temperature:
bacteria with wide optimum temperature range are called
eurithermophilic
Example of sternothermophilic bacteria
Neisseria spp. (36.5-37.5C)
Example of eurithermophilic bacteria
Enterococcus spp. (10-45C)