Cross Index Flexibacter
SuperSet Prokaryote, Eubacteria Gliding Bacteria
Compare Cytophagales, Beggiatoales

Single Celled, rod shaped Capnocytophaga, Chitinophaga pinensis , Cytophaga, Flexibacter, Flexithrix dorotheae, Lysobacter, Microscilla, Sporocytophaga myxococcoides, Thermomena,
Flattened, filamentous Gliding: Alysiella filiformis, Simonsiella,
Sulfur oxidizing,Gliding: Achromatium, Beggiatoa alba, Thioploca, Thiospirillopsis floridana, Thiothrix nivea,
The Pelonemas: Achroanema spp, Desmanthos thiorenophilum, Pelenema, Peloploca,
Other Genera: Agitococcus lubricus , Desulfonema Herpetosiphon, Isosphaera pallida, Leucothrix mucor, Saprospira, Toxothrix trichogenes,Vitreoscilla

Contrast Archaea


Morphology Flexibacter
Staining Gram -negative
Morphology Rod-shaped cells of variable length, typically 10-50 um long, slender, 0.2-0.6 um wide, flexible, and with tapering or rounded ends
Motility Gliding, but nonmotile stages may occur. In some species
Specialized structures there is a (cyclic) change in cell morphology. In young liquid cultures or on plates at the edge of spreading colonies or swarms, the cells are thread-like, 20-50 um and more in length,and very agile, actively twisting and bending. As these cells have no cross-walls or, at best, very few cross-walls, they will be called thread cells to distinguish them from multicellular filaments. In aging cultures or behind the swarm edge, the cells become shorter and shorter until only short, stout, nonmotile and phase-dark rods are left, clearly fatter than the thread cells, sometimes almost coccoid
Solid surface Cell mass usually yellow to orange, sometimes very pale or even colourless. The pigments are cell- bound and often carotenoids and/or of the flexirubin type. In the latter case, the colonies show an immediate and reversible colour change to red-brown or purple when covered with alkali solution (eg. 20% KOH; reversed by 10% HCl).


Growth Parameters Flexibacter
Tropism Chemoorganotrophs
Oxygen Strictly aerobic or facultatively anaerobic
Requirements Peptones and amino acid mixtures serve as nitrogen sources. Various sugars are utilized. Some grow on simple defined media, eg. with glucose and NH4+. Cellulose and agar are not attacked, but chitin and starch are often degraded.
Unique features  
Habitat Organisms widely distributed and common in soil and freshwater


Genome Flexibacter
G+C Mol % 37-47


Reference Flexibacter
First citation Soriano,S. 1945. Un nuevo orden de bacterias: Flexibacteriales. Cienc. Invest. B. Aires 1:92-93
Emended H. Reichenbach 1989 Flexibacter: in Bergey's Manual of systematic Bacteriology Vol 3 ( James T. Stanely Editor, Marvin P. Bryant, Norbert Pfennig, associate Editor, John G. Holt Editor-in-chief p 2061 ISBN-0-683-07906-5
The Prokaryotes  
Bergey's Systematatic p 2061 H. Reichenbach
Bergey's Determinative p 487