The L. hongkongensis genome lacks a complete set of enzymes for glycolysis, with orthologues of glucokinase, 6-phosphofructokinase and pyruvate kinase being absent (Table S1 ). This is compatible with its asaccharolytic phenotype and is consistent with other asaccharolytic bacteria, such as Campylobacter jejuni, Bordetella pertussis, Bordetella parapertussis and Bordetella bronchiseptica, in that glucokinase and 6-phosphofructokinase are also absent from their genomes [18, 19] . On the other hand, the L. hongkongensis genome encodes the complete sets of enzymes for gluconeogenesis, the pentose phosphate pathway and the glyoxylate cycle (Table S1) . Similar to C. jejuni, the L. hongkongensis genome encodes a number of extracellular proteases and amino acid transporters. These amino acids can be used as carbon source for the bacterium. The genome encodes enzymes for biosynthesis of the 21 genetically encoded amino acids and for biosynthesis and b-oxidation of saturated fatty acids (Tables S2 and S3 ). The L. hongkongensis genome encodes a variety of dehydrogenases (LHK_00527-00540, LHK_01219-01224, LHK_02418-02421, LHK_00801-00803, LHK_01861, LHK_02912-02913 and LHK_00934) that enable it to utilize a variety of substrates as electron donors, such as NADH, succinate, formate, proline, acyl-CoA and D-amino acids. The presence of three terminal cytochrome oxidases may allow L. hongkongensis to carry out respiration using oxygen as the electron acceptor under both aerobic conditions [type aa 3 oxidase (LHK_00169-00170, LHK_00173)] and conditions with reduced oxygen tension [type cbb 3 (LHK_00995-00996, LHK_00998) and type bd (LHK_02252-02253) oxidases]. The genome also encodes a number of reductases [fumarate reductase (LHK_02340-02342), nitrate reductase (LHK_02079-02085), dimethylsulfoxide (DMSO) reductase (LHK_02496-02498) and tetrathionate reductase (LHK_01476-01478)], which may help carry out respiration with alternative electron acceptors to oxygen (fumarate, nitrate, DMSO and tetrathionate) under anaerobic conditions. This is supported by the enhanced growth of L. hongkongensis under anaerobic conditions in the presence of nitrate (data not shown). Further studies are required to confirm if the bacterium can utilize other potential electron acceptors.