Figure 5.

FA acquisition in a S. pneumoniae ΔfakB3 deletion strain. A, schematic diagram illustrating the construction of strain JMG1 (ΔfakB3). The final construct has the fakB3 gene replaced with a cassette expressing kanamycin resistance. Primers 1 and 6 showed the exchange of the fakB3 gene for the kanamycin cassette, and primers 7 and 8 confirmed that fakB3 was absent from the genome. Construction details are provided under “Experimental procedures” and primer sequences are listed in Table 1. B, representative spectra of S. pneumoniae strain JMG1 (ΔfakB3) grown in C+Y media (C) and grown in 50% human serum, 50% C+Y medium human serum. D, TIGR4, JMG1 (ΔfakB3), and JMG1/pSpFakB3 were grown in 50% human serum, 50% C+Y medium, PG mass spectra from triplicate biological replicates were obtained, the areas under each peak in the spectra were summed, the molecular species containing 18:2 as a percent of the total area were calculated, and the mean ± S.D. was plotted.