purple bacteria(n = noun.animal) - free-living Gram-negative pink to purplish-brown bacteria containing bacteriochlorophyll;
is a kind of phototrophic bacteria, phototropic bacteria

bacteria, bacteria bed, bacteria family, bacteria genus, bacteria order, bacteria species, banded purple, early purple orchid, endospore-forming bacteria, enteric bacteria, gliding bacteria, late purple aster, nitric bacteria, nitrous bacteria, order of the purple heart, penicillin-resistant bacteria, phototrophic bacteria, phototropic bacteria, potato scab bacteria, purple, purple amaranth, purple anise, purple apricot, purple avens, purple beech, purple boneset, purple chinese houses, purple clematis, purple clover, purple cress, purple emperor, purple finch, purple fringeless orchid, purple fringeless orchis, purple gallinule, purple grackle, purple granadillo, purple ground cherry, purple heart, purple heather, purple loco, purple locoweed, purple loosestrife, purple martin, purple milk vetch, purple mullein, purple nightshade, purple onion, purple orchis, purple osier, purple passage, purple pea, purple poppy mallow, purple rock brake, purple sage, purple sanicle, purple saxifrage, purple silkweed, purple strawberry guava, purple trillium, purple velvet plant, purple virgin's bower, purple willow, pus-forming bacteria, red-spotted purple, reddish purple, retinal purple, ring rot bacteria, royal purple, slime bacteria, sulfur bacteria, sulphur bacteria, texas purple spike, true bacteria, tyrian purple, visual purple