Co-cultivation of selected combinations of HOB and MOB

The eight best combinations were selected based on the plating of the combinations of the 9 MOB with the 19 HOB. Additionally, X. autotrophicus and C. necator were combined with the best growing MOB, Methyloparacoccus murrelli LMG 27482, as established by the results of plating and flow cytometry measurements. C. necator is one of the most well-described species for hydrogen-driven MP production (Yu, 2018), whereas we recently identified X. autotrophicus as a autotrophic, nitrogen fixing HOB (Hu et al., 2020). As before, the MOB and HOB pure cultures were diluted in DSMZ medium 81 containing trace elements, at a final cell density of 106 cells/mL, before being subjected to triplicate incubations