Riemerella

Abstract

Rie.me.rel'la. N.L. fem. n. Riemerella named in honor of O.V. Riemer, who first described Riemerella anatipestifer infections in geese in 1 9 0 4 and referred to the disease as septicemia anserum exsudativa (Riemer, 1904). Bacteroidetes / Flavobacteriia / Flavobacteriales / Flavobacteriaceae / Riemerella The following description is based on those given by Segers et al. (1993a) and Vancanneyt et al. (1999). Rods , 0 . 2–0 . 5 × 1 . 0–2 . 5 μ m . Nonmotile. No gliding motility. Nonspore‐forming. Gram‐stain‐negative. All strains grow microaerobically and most of them grow aerobically on blood agar . Some strains grow anaerobically at 37°C. Colonies are smooth and nonpigmented or grayish‐white to beige. Growth on litmus lactose agar is strain‐dependent. No growth occurs on MacConkey agar. Most strains show a positive Voges–Proskauer reaction. Nitrates are not reduced. Acid production from glucose is frequently negative in peptone‐containing media . The following enzymes are present: oxidase , catalase , gelatinase, α‐glucosidase, α‐maltosidase, alkaline phosphatase, acid phosphatase, esterase lipase C8, esterase C4, naphthol‐AS‐Bl‐phosphohydrolase, leucine arylamidase, valine arylamidase, cystine arylamidase, and L ‐aspartic acid arylamidase. The following reactions are strain‐dependent: urease, chymotrypsin, trypsin, arginine dihydrolase, indole production, hemolysis on blood, and esculin hydrolysis. Depending on the micro‐test kit used, the following enzyme reactions give variable results: β‐glucosidase, α‐galactosidase, and lipase (these three reactions are positive in the API ID32E and negative in the API ZYM system); and N ‐acetyl‐β‐glucosaminidase [negative in API ZYM and API ID32E, positive in LRA‐ZYM‐Oxidase (Hinz et al., 1998); only some representative Riemerella anatipestifer strains have been tested using the latter system]. The following enzyme activities are absent: chondroitin sulfatase, hyaluronidase, β‐galactosidase, β‐glucuronidase, α‐mannosidase, α‐fucosidase, trypsin, ornithine decarboxylase, and lysine decarboxylase. None of the strains use malonate as a carbon source or assimilate the following compounds (API 20NE system): D ‐glucose, L ‐arabinose, D ‐mannose, D ‐mannitol, N ‐acetylglucosamine, maltose, D ‐gluconate, caprate, adipate, L ‐malate, citrate, or phenylacetate. No acid production occurs with the following (API ID32E system): D ‐ and L ‐arabitol, galacturonate, 5‐ketogluconate, phenol red, D ‐mannitol, maltose, adonitol, palatinose, sucrose, L ‐arabinose, trehalose, rhamnose, inositol, sorbitol, and cellobiose. Using the buffered single substrate (BSS) test, however, acidification of the following carbohydrates may be detected: D ‐glucose, maltose, D ‐mannose, and dextrin and, to a lesser extent, D ‐fructose, L ‐sorbose, and trehalose, but no acid is produced from lactose, D ‐galactose, N ‐acetyl‐ D ‐glucosamine, lactulose, trehalose, sucrose, D ‐mannitol, L ‐arabinose, myo ‐inositol, D ‐sorbitol, D ‐xylose, dulcitol, salicin, or adonitol. Menaquinone‐6 is the major respiratory quinone detected in the type species. The dominant fatty acids are the branched‐chain fatty acids C 13:0 iso, C 15:0 iso, C 15:0 anteiso, C 15:0 iso 3‐OH, and C 17:0 iso 3‐OH. Isolated mainly from diseased birds and, in a few cases, from pigs. DNA G + C content ( mol %): 29–37. Type species : Riemerella anatipestifer (Hendrickson and Hilbert 1932) Segers, Mannheim, Vancanneyt, De Brandt, Hinz, Kersters and Vandamme 1993a, 775 VP [ Moraxella anatipestifer (Hendrickson and Hilbert 1932) Bruner and Fabricant 1954, 461; Hemophilus anatipestifer Hauduroy, Ehringer, Urbain, Guillot and Magrou 1937, 247; Pasteurella anapestifer ( sic ) Hauduroy, Ehringer, Guillot, Magrou, Prévot, Rosset and Urbain 1953, 367; Pasteurella anatipestifer (Hendrickson and Hilbert 1932) Breed, Murray and Smith 1957, 397; Pfeifferella anatipestifer Hendrickson and Hilbert 1932, 249].