test 3 lecture 17 Flashcards
(32 cards)
how are microbial species defined for eukaryotes
members of different species do not normally interbreed
how are microbial species defined for archaea and bacteria
reproduce asexually so interbreeding is not a basis for classification and there can be horizontal gene transfer
what do microbiologists accept for defining species
phylogeny and ecology
what is ecological niche
a species should include individuals that share common traits and ecological niche or ecotype
such as cell shape, nutritional reqs, common habitat, common life history
what is phylogenic relatedness
a species is a group of individuals that share relatedness of a key set of “housekeeping genes”
what are “housekeeping genes”
informational gens such as ribosomal and transcriptional components
should be orthologs
what is a pangenome
the theoretical total
genes present in all sequenced genomes of a species
core genome accessory genes
taxonomy
the description of distinct life forms and their organization into different categories with shared traits
classification
the recognition of different classes of life
nomenclature
the naming of different classes
identifications
the recognition of the class of a given microbe isolated in pure culture
what does emerging mean
an organism recently discovered or described
what is a phylum
a group of bacteria sharing a common ancestor that diverged early from other bacteria, based on the SSU rRNA
what is practical identification
based on a combination of phylogenetic and phenetic traits
what are some common traits of bacteria
rna polymerase
rRNA
translation factors
what is in a bacterial cell wall and not archaea and eukaryotes
peptidoglycan
what antibiotics target cell wall
vancomycin and penicillin
proteobacteria share what common structure
gram neg cell envelope
what does the gram neg cell envelope consist of
outer membrane
cell wall
inner cell membrane
how many classes are in proteobacteria
5
what are photoheterotrophs
capable of light supplemented heterotrophy
alphaproteobacteria consist of
photoheterotrophs
aquatic and soil oligotrophs
methylotrophs and methanotrophs
endosymbionts
what is special about aquatic and soil oligotrophs of alpha group
adapt to low nutrient concentrations
unusual extended shapes for nutrient uptake
some are pathogens
what are methylotrophs
oxidize reduced single carbon compounds such as methanol
can grow on single carbon and organic molecules
