true bacteria - a large group of bacteria having rigid cell walls; motile types have flagellamoneran, moneron - organisms that typically reproduce by asexual budding or fission and whose nutritional mode is absorption or photosynthesis or chemosynthesis Bacilli, Bacillus, B - aerobic rod-shaped spore-producing bacterium; often occurring in chainlike formations; found primarily in soil cocci, coccus - any spherical or nearly spherical bacteria coccobacillus - a bacterial cell intermediate in morphology between a coccus and a bacillus; a very short bacillus spirilla, spirillum - any flagellated aerobic bacteria having a spirally twisted rodlike form division Eubacteria - one-celled monerans having simple cells with rigid walls and (in motile types) flagella clostridia, clostridium - spindle-shaped bacterial cell especially one swollen at the center by an endospore clostridium perfringens - anaerobic Gram-positive rod bacterium that produces epsilon toxin; can be used as a bioweapon blue-green algae, cyanobacteria - predominantly photosynthetic prokaryotic organisms containing a blue pigment in addition to chlorophyll; occur singly or in colonies in diverse habitats; important as phytoplankton pseudomonad - bacteria usually producing greenish fluorescent water-soluble pigment; some pathogenic for plants and animals xanthomonad - bacteria producing yellow non-water-soluble pigments; some pathogenic for plants thiobacillus - small rod-shaped bacteria living in sewage or soil and oxidizing sulfur spirillum - spirally twisted elongate rodlike bacteria usually living in stagnant water listeria - any species of the genus Listeria rickettsias - rod-shaped microorganisms resembling both bacteria and viruses; live in biting arthropods and cause disease in vertebrate hosts chlamydia - coccoid rickettsia infesting birds and mammals; cause infections of eyes and lungs and genitourinary tract mycoplasma - the smallest self-reproducing prokaryote; lacks a cell wall and can survive without oxygen; can cause pneumonia and urinary tract infection actinomycete - any bacteria (some of which are pathogenic for humans and animals) belonging to the order Actinomycetales actinomyces - soil-inhabiting saprophytes and disease-producing plant and animal parasites lactobacillus - gram-positive rod-shaped bacteria that produce lactic acid especially in milk flagellum - a lash-like appendage used for locomotion (e.g., in sperm cells and some bacteria and protozoa) |