Taxonomy/systematics Dysgonomonas hofstadii sp. nov., isolated from a human clinical source Paul A. Lawson a, * , Petteri Carlson b , Sofia Wernersson c , Edward R.B. Moore c , Enevold Falsen c a Department of Botanyand Microbiology, University of Oklahoma, 770 Van Vleet Oval, Norman, OK 73019, USA b Kymintie 37, FI-00560 Helsinki, Finland c CCUG – Culture Collection University of Go ¨teborg, Department of Clinical Bacteriology, Sahlgrenska University Hospital, University of Go ¨teborg, Go ¨teborg S-413 46, Sweden article info Article history: Received 23 April 2009 Received in revised form 16 June 2009 Accepted 24 June 2009 Available online 1 July 2009 Keywords: Dysgonomonas hofstadii sp. nov. Facultative anaerobe 16S rRNA Phylogeny Taxonomy abstract A Gram-negative staining, facultative anaerobic, cocco-bacillus-shaped organism was isolated from a post-operative abdominal wound. Based on morphological and biochemical criteria, strain MX 1040 ( ¼ CCUG 54731 T ) was tentatively identified as Bacteroidaceae but did not correspond to any recognized species of this family. Comparative 16S rRNA gene sequencing analysis demonstrated the organism to be related to species of the genus Dysgonomonas, although sequence divergence values of >5% with the other members of this genus demonstrated the organism to represent a novel species. Phylogenetic analysis revealed the novel organism to be most closely related to Dysgonomonas gadei. The major long- chain cellular fatty acids of the novel species consisted of iso-C 14:0 , anteiso-C 15:0 ,C 16:0 , and iso-C 16:0 . Based on the phenotypic criteria and phylogenetic considerations, it is proposed that strain MX 1040 from a human clinical source represents a new species of the genus Dysgonomonas, as Dysgonomonas hofstadii sp. nov. The type strain of D. hofstadii is CCUG 54731 T ( ¼ CCM 7606 T ). Ó 2009 Elsevier Ltd. All rights reserved. 1. Introduction The genus Dysgonomonas was created by Hofstad et al. [1] to accommodate Gram-negative, facultative anaerobic cocco-bacillus- shaped bacteria. As the genus presently stands, it contains three species, Dysgonomonas gadei, Dysgonomonas capnocytophagoides and Dysgonomonas mossii .These fastidious organisms were recovered from human sources and form a distinct phylogenetic cluster within the Bacteroides–Prevotella–Porphyromonas group of the phylum ‘‘Bacteroidetes’’. The organisms characteristically produce straight- chain saturated anteiso- and iso-methyl branched and 3-hydroxy long-chain cellular fatty acids [3]. In the course of a continuing study of taxonomically problematic Gram-negative organisms from human sources, a strain of uncertain taxonomic position was isolated from a clinical sample of a wound after abdominal surgery in Helsinki, Finland, and deposited with the Culture Collection – University of Go ¨teborg (CCUG). In addition to the novel isolate described in this article, the sample from the wound also contained a mixed-culture that consisted of Candida albicans, Bacteroides fragilis and Pseudo- monas aeruginosa. Based on the results of a polyphasic taxonomic study, we describe and propose a fourth species of Dysgonomonas, Dysgonomonas hofstadii 1 sp. nov. 2. Materials and methods 2.1. Cultures and cultivation Strain MX 1040 ( ¼ CCUG 54731 T ) was originally isolated from a wound following abdominal surgery, taken from a 72-year-old male patient at Helsinki University Central Hospital, Department of Abdominal Surgery, Helsinki, Finland. The unidentified isolate was cultivated using a number of media that included chocolate and blood agar under anaerobic and aerobic conditions as described in Section 3. 2.2. Phenotypic characterisation Growth requirements for X and V factors were examined using discs impregnated with X factor, V factor, or both, and nutrient agar as basal medium. These growth factors are often used to determine a requirement for haem and can be used in the differentiation of Gram-negative organisms such as Haemophilus and Bacteroidaceae. X factor is comprised of protoporphyrin IX, haemin or other iron- containing porphyrins. These are required for growth because X-dependent strains are unable to convert d-aminolaevulinic acid to protoporphyrin. V factor comprises nicotinamide adenine dinucleotide (NAD) or nicotinamide adenine dinucleotide phos- phate (NADP) 2 . The strains were biochemically characterised by using a combination of conventional tests, following the protocol of the CCUG Typing Laboratory for anaerobic and facultative anaerobic * Corresponding author. Tel.: þ1 405 325 4426; fax: þ1 405 325 7619. E-mail address: paul.lawson@ou.edu (P.A. Lawson). 1 The GenBank/EMBL accession number for the 16S rRNA sequence of Dysgono- monas hofstadii CCUG 54731 T is FN356023. Contents lists available at ScienceDirect Anaerobe journal homepage: www.elsevier.com/locate/anaerobe 1075-9964/$ – see front matter Ó 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.anaerobe.2009.06.005 Anaerobe 16 (2010) 161–164