Lecture 7: Tree of Life and bacterial diversity Flashcards
what did Carl Woese base his tree of life off of?
quantitative relatedness via ribosomes and ribosomal RNA
how many rRNAs are enough to get good data?
16
what are the 5 important Eukaryotic Signature Proteins (ESPs)?
- eukaryotic like actin
- many small GTPases
- endosomal sorting complex required for transport (ECRT)
- membrane deformation and phagocytosis ESPs
- ubiquitin
what colour do gram positive bacteria stain as?
purple due to more peptidoglucan
what colour do gram negative bacteria stain as?
pink due to a thin layer of peptidoglucan
what are gram negative bacteria also known as?
proteobacteria
what 5 categories are proteobacteria subdivided into?
alpha, beta, gamma, delta, epsilon
what are the features of proteobacteria?
- metabolically diverse
- many environmental habitats (symbionts, nitrogenous, aquatic)
- human pathogens exhibit chemotrophy
what are the alpha proteobacteria also know as?
rhizobales
what do the rhizobales (alpha) do?
form symbiosis with plants, fix nitrogen to ammonia
what are the beta proteobacteria also known as?
neisseriales
what do the neisseriales (beta) do?
medically important eg. meningitis and gonorrhoea
what are the gamma proteobacteria also known as?
enterobacteriales
what do the enterobacteriales (gamma) do?
salmonella food poisoning and E.coli
what are the delta proteobacteria also known as?
spirilla
what do the spirilla (delta) do?
curved bacteria that are potential antimicrobials acting as vampire like bacterial predators
what are epsilon proteobacteria also known as?
campylobacterales
what do campylobacterales do?
highly motile curved bacteria found to cause foodbourne disease
what is unique about helicobacter?
have multiple flagella and cause stomach ulcers
what 2 categories are gram positive bacteria divided into?
Low G+C and High G+C depending on G+C content of the genome
what are low G+C bacteria known as?
firmicutes
what are high G+C bacteria known as?
actinobacteria
what are 5 relevant firmicutes?
- Lactobacillus: used for fermented yogurt
- Streptococcus: known as strep throat
- Staphylococcus: produces boils and MRSA
- Bacillus: anthrax and can survive extremes due to endospore forming
- Clostridium: lockjaw and diarrhoea
what are 3 relevant actinobacteria?
- actinomyces: soil ecology
- frankia: nitrogen -> ammonia
- streptomyces: produce antibiotics
what does FISH stand for?
Fluorescent in situ hybridisation
