Table 2 Swarming and Planktonic Growth of V. paradoxus EPS Broth Growth (24 h) Swarminga Biofilm Carbon Sources M9 FW M9 FW M9 Casamino acids ++ ++ ++ ++ +++ Glucose ++ +/- + +/- ++ Succinate ++ ++ ++ ++ +++ Benzoate ++ ++ – - +/- Maltose ++ – +* – +/- Sucrose ++ – + – + d-Sorbitol
++ – ++ +/- ++ Maleic acid + – - – +/- Mannitol ++ – ++ – + Malic acid ++ – ++ +/- ++ Nitrogen Sources (with Succinate) NH4Cl ++ ++ ++ ++ + NH4SO4 ++ ++ ++ ++ + Tryptophan ++ + ++ ++ + Histidine ++ + ++ ++ + Methionine ++ – + + + Cysteine – nd Nd Nd nd Tyrosine ++ – + + + Arginine ++ nd + + + Glycine ++ – +/- + + * swarming was slower with distinct edge (Fig 3, 4) Figure 5 Nutrient dependence of swarming motility. A) Swarm diameter at 24 h (blue bars) or 48 h (red bars) using several carbon sources on FW (F) or M9 (M) base. F/M-S = succinate, F/M-G = glucose, F-G-P = glucose + 2 mM phosphate buffer (pH7), M-M = maltose, F/M-CAA = casamino acids (C+N), PRIMA-1MET clinical trial M-Ma = malic acid, M-So = sorbitol, M-Su = sucrose. * indicates that IWR-1 concentration swarms merged by 48 h. B) Swarm diameter at 24 h (blue bars) or 48 h (red
bars) using several nitrogen sources on FW (F) or M9 (M) base. All swarms measured in triplicate, with error in all cases ± SEM. Figure 6 Edges of swarms are affected by nutrients, basal medium. Swarming edge images after 24 h on a variety of media. FW base medium was used for (A, B, D, J, K, L) with M8/M9 base medium used for the other panels. Succinate is the C source in all panels except B (glucose) and C (maltose). For growth on Etofibrate FW-glucose, 2 mM NF-��B inhibitor sodium phosphate buffer (pH 7) was added. NH4Cl was the N source in (A-C), with alternative N sources methionine (D, E), arginine (F), tyrosine (G, J), tryptophan (H, K), and histidine (I, L). Arrows point to extruded material from swarm edges under certain conditions. Scale bar = 25 microns.
Figure 7 Gross swarm morphology is affected by nutrients, basal medium. Colony morphologies after 1d on A) FW-succinate-NH4Cl and B) FW-casamino acids. C) After 3d on FW-succinate-methionine, a “”rare branch”" phenotype was observed. D) Slower swarming on M9-succinate-tyrosine was characterized by a less well defined swarm with altered structure. Stark differences in extent and form of swarming were observed on E) FW-succinate-tryptophan and F) M9-succinate-tryptophan. G) After an extended incubation, swarms on FW-succinate-NH4Cl display a mutually repellent morphology with distinct internal and external edges. Swarming motility on different nitrogen sources When succinate was used as carbon source, all single amino acids tested were permissive for swarming on FW minimal base as well as M8 base (Table 2). When the swarm diameters were measured at 24 h and 48 h, a pattern similar to the carbon source experiments was observed (Fig 5B). Rapid swarming was observed on NH4Cl, tryptophan, histidine, and glycine (Fig 5B).