Effect of the hps/phi Copy Number on the Growth of Methylococcus capsulatus MIR

Methylococcus capsulatus MIR is a biotechnologically promising strain of methanotrophic bacteria for obtaining feed protein and other value-added products from methane. This strain assimilates methane carbon mainly via the ribulose monophosphate pathway, the key enzymes of which are 3-hexulose-6-phosphate synthase and 6-phospho-3-hexulose isomerase. It was shown that the presence of one, two, or three copies of the genes encoding hexulose phosphate synthase/isomerase affected the level of the total gene expression but did not affect the growth characteristics of the strain and did not correlate with the protein content in the cells. The data obtained indicate that fixation of formaldehyde by hexulose phosphate synthase is not the reaction limiting the growth of bacteria of the genus Methylococcus.