You Have Found The Satan...!
Characteristics : Bent and irregularly - coiled filaments, 0.6 - 0.8 micron in diameter and 100 - 200 micron in
length, found within the flocs and free in the bulk solution. Cell septa are hard to observe; when observed, cells are
oval (0.6 - 0.8 micron in diameter). No sheath and no attached growth. Gram positive and Neisser - positive trichome. No
sulfur granules. Resembles M.parvicella, except in Neisser - staining properties.
Identification : Medium length, non-motile filaments (100-200 µm). Bent and irregularly coiled filaments with
incidental true branching. Cell septa are hard to observe. Cells are ovoid or disc shaped (0.6-0.8 µm). Filaments are
found within the floc structure but may occur in the bulk solution. The filament staining is variable, it is usually
Gram positive and Neisser positive. There is no sheath and there are no sulfur granules. No Poly-ß-hydroxybutric acid
(PHB) granules observed. Attached growth is usually uncommon.
Similar Organisms : Three subtypes are known. Resembles M. parvicella except in its Neisser staining properties.
Environment : This filament is usually found in environments where there is low DO or low F/M and the presence of
organic wastes. Wastes containing starch seem more selective to this filament. Bulking is more common in industrial wastes.
The filament appears to be facultative fermentative, which is unique for most filaments.
Control : Manipulation of F/M (usually an increase) and DO concentration can be used to control the filaments.
A selector may be used and chlorination. System changes include changing from a complete mix to plug flow aeration basin
configuration.
Rank : N. limicola ranks 12th in number of predominance. Typically not found in kraft mills.
