Conceived and designed the experiments: SJ, HF, AT, IS, ML, CB, JE, LFW, PD, SN. Performed the experiments: SJ, HF, CdJ, KO, GM, AT, TH, AB, JB, RA, LR, AF, MY, MC, JE, SN. Analysed the data: HF, CdJ, KO, GM, AT, JB, AF, MY, MC, JE, LFW. Contributed particular reagents/materials/analysis tools: GM, TH, JB, RA, LR, AF, MY. Wrote the paper: SJ, HF, CdJ, KO, GM, AT, TH, AB, JB, RA, LR, AF, MY, MC, IS, ML, CB, JE, LFW, PD, SN. Coordinated and facilitated the project: SJ, HF, AT, TH, AB, RA, IS, ML, CB, JE, LFW, PD, SN. All authors read and approved the final manuscript.