A new ethylenediaminetetraacetic acid (EDTA)-utilizing gammaproteobacterial strain LPM-5(T) was isolated from municipal sewage sludge. Aerobic, gram-negative, motile rods multiply by binary fission. Neutrophilic and mesophilic, these are unable to grow in the presence of 3% NaCl (w/v), and unable to reduce nitrate to nitrite, and are oxidase and catalase positive, but lipase negative. The major cellular fatty acids are C-i15:0, C-a15:0 and C-16:1w7c. The dominant phospholipids are phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol (cardiolipin). The DNA G + C content is 68.3 mol% (T-m). The 16S rRNA gene sequence analysis showed a high similarity of strain LPM-5(T) to the species members of genus Stenotrophomonas: S. maltophilia LMG 958(T) (98.6%), S. rhizophila CCUG 47042(T) (98.3%), S. koreensis TR6-01(T) (97.6%) and S. acidaminiphila CIP 106456(T) (97.0%). Based on these results and modest DNA-DNA hybridization levels with S. maltophilia VKM B-591(T) (= LMG 958(T)) (51%) and S. rhizophila CCUG 47042(T) (52%), the isolate was classified as a novel species, Stenotrophomonas chelatiphaga sp. nov. (type strain LPM-5(T) = VKM B-2486 = DSM-21508 = CCUG 57178). (C) 2009 Elsevier GmbH. All rights reserved.