Section C

cyannobacteria neurotoxin

cyanophycin

cyano bacteria cels for nitrogen fixation

heterocyst

purple sulphur bacteria

anoxygenic phototrophic geemproteobacteria

what does Purple sulphur bacteria do ?

oxidizes hydrogen sulphur to elemental sulphur , storing sulphur intracelllularly or extracellularly and late converting it to sulphate

where is Purple sulphur bacteria found

sulphur-rich environments forming blooms or biofilms

what to Purple sulphur bacteria contain

bacteriochlorophyll and carotenoids giving purple re brown colour

how does it grow

anerobically in the dark by fermentation or arobically by respiration

where do Purple non-sulphur bacteria grow

anaerobic conditions in light using organic compounds as electron donors and can gro aerobically in the dark by respiration

where are Purple non-sulphur bacteria found

mud, stagnant water, shallow anaerobic aquatic environments exposed to light but low sulphade

extremeley halophillic archaea

require very high salt concentrations for grow; thirve in salt lakes, salted fish, solar salterns

Extremely halophilic archaea contain:

high in potatssium to balance the osmotic pressure from external salt

specialised proteins and enzymes that remain functional in high-salt conditions

carotenoid pigments give it pink colour

bdellovibrio

gram-negative, small, highly motile, curved oblligate aerobe that uses the oxidation of amino acids and acetate from the host for energy

what does bdellovibrio do

attacks other gram-negative bacteria by attracting to the cell wall, penetrating the outer membrane and replicating the periplasmic space. inside the host, it forms a structure called a bdelloplast consuming the host and causing lysis after replication

where are bdellovibrio found

soil freshwater seawater and isolated on bacterial lawns

eneterobacteriaceae

gram-negative facultative anaerobic rods commonly found in the intestinal tracts of animals characterised by being oxidase negative, nitrate reducers and fermenting glucose with acid and gas production

used in diagnostic during IMVIC test

many are pathogenic causing gastroenteritis or UTIs

eneterobacteriaceae members

salmonella, shingella, enterobacter