Phenotypic characterization. Strains were grown on M9 solid medium (Abril et al.,
1989) supplemented with 0.1% (w/v) glucose. The following day cells were recovered
with a loop and resuspended in M8 minimal medium. The wild-type and the mutant
strains were inoculated into microwell plates in M9 minimal medium with different
carbon (5 mM), nitrogen (5 mM) and sulphur (5 mM) sources, and growth at 30ºC with
continuous shaking was monitored using Bioscreen C (ThermoFisher Scientific) at 420580 nm for 24 hours. Minimal M9 medium was prepared as in Abril et al. (1989)
however, when appropriate, MgSO4 or NH4Cl was replaced with other sulphur or
nitrogen sources. Carbon sources: D-glucose, D-fructose, D-glucuronic acid, glycerol,
sodium acetate, trisodium citrate, fumaric acid, sodium succinate, sodium lactate, malic
acid, sodium pyruvate, methyl pyruvate, propionic acid, sodium benzoate, sodium 4hydroxybenzoate, quinic acid,
aminobutyric acid, 5-amino-n-valeric acid, 2,4-
dihydroxyphenylacetic acid, sodium decanoate, Tween 20, 2-phenylethanolamine, LLeu, L-Lys, L-His, L-Gln, L-Glu, L-Phe, L-Arg, L-Asn, L-Ala, L-Pro, L-Tyr, L-Ile, LCys, L-Met, L-Val, glutaric acid, and xylose. Nitrogen sources: D- and L-Arg, D- and
L-Lys, D- and L-Pro, D- and L-Val, D- and L-Ala, D- and L-Asn, D-Met, D-Leu, LAsp, L-Cys, L-Phe, L-Glu, L-Gln, L-Gly, L-His, L-homoserine, L-Ile, L-trans
hydroxyproline, L-Ser, L-Tyr, Ala-Glu, Ala-Gly, Ala-His, Ala-Leu, Ala-Phe, Gly-Gln,
Gly-Gly, Gly-Leu, Gly-Ser, Gly-Val, Tyr-Ala, adenine, agmantine sulphate,
hypoxanthine, phenylethanolamine, ethanolamine, putrescine, D,L-ornithine, NH4Cl,
NH4NO3 and urea. Sulphur sources: L-Cys, D- and L-Met, L-cystine, cysteamine, D,L-
ethionine, D,L-homocysteine, taurine, thiourea, 2-thiouracil, N-acetyl-cysteamine, 2thiohidanthoin, sodium taurocholate, agmantine sulphate, Na2SO4, and Na2SO3.
For stress experiments all strains were grown overnight in 1/5 LB medium plates
(tryptone [2gr/l], yeast extract [1g/l], NaCl [2g/l] and agar [15 g/l], resuspended in M8
minimal media as before and inoculated in ½ LB liquid medium [LB liquid medium and
water, 1:1]) plus the corresponding stressor. Stressors used were: Antibiotics: ampicillin
(Ap) 10 μg/ml; carbenicillin (Cb) 80 μg/ml; chloramphenicol (Cm) 15 μg/ml;
cefotaxime (Ctx) 0.375 μg/ml; erythromycin (Ery) 15 μg/ml; gentamycin (Gm) 2 μg/ml;
kanamycin (Km) 0.195 μg/ml; nalidixic acid (Nal) 0.012 mg/ml; neomycin (Neo) 1
μg/ml; norfloxacin (Nor) 0.05 μg/ml; novomycin (Nov) 100 μg/ml; piperacillin (Pip) 10
μg/ml; rifampicin (Rif) 30 μg/ml; streptomycin (Sm) 2 μg/ml; spectinomycin (Sp) 0.1
mg/ml; and tetracycline (Tc) 5 μg/ml. Heavy metals and metaloids: AgNO3 (3 mM),
CdCl2 (1.56 mM), CoCl2 (0.156 mM), CuSO4 (1 mM), LiCl (0.25 mM), MnSO4 (1 mM),
NiCl2 (1 mM), RbCl (6.2 μM), K2TeO3 (0.975 μg/ml); KH2AsO4 (0.9 mg/ml) and ZnCl2
(0.5 mM). Detergents and protein solubilising agents: Cetyl trimethylammonium
bromide (CTAB), 0.001%; N-lauroyl sarcosine (NLS), 0.078%; sodium dodecyl sulfate
(SDS), 0.06%; deoxycholate (DOC), 1%; triton X-100 (1%) and non-detergent
sulphobetaines (NDSB-201), 1%. Chelating agents: ethylenediaminetetraacetic acid
(EDTA), 0.125 mM and 2,2'-bipyridyl (Bip) (0.5 mM). Osmotic stress agents: NaCl
(0.5 M). Oxidative stress: K2Cr2O7, 12.5 μg/ml; H2O2, 0.004%; NH2OH, 30 μg/ml;
methyl viologen (MV), 100 μM; tert-butyl hydroperoxide (TBH), 0.0015%. Others:
Ethidium bromide (EtBr) 0.1 mg/ml; KCN 0.325 mg/ml and KSCN (80 mM) and NaBr
(0.25 M).