The Impact of Pyroglutamate: Sulfolobus acidocaldarius Has a Growth Advantage over Saccharolobus solfataricus in Glutamate-Containing Media

Figure 1

The growth of Sulfolobus acidocaldarius and Saccharolobus solfataricus on L-glutamate and measured amino acid concentration in the medium. Both strains, S. acidocaldarius MW001 (dots) and S. solfataricus P2 (triangles), were grown in Brock medium containing 24 mM L-glutamate as a sole carbon source. (a) Growth curve following the cell dry weight per litre of medium S. acidocaldarius (dots) and S. solfataricus (triangles). Curves were fitted with logistic regression in R. (b) Glutamate (black) and pyroglutamate (red) concentration in supernatant during growth of S. acidocaldarius MW001 (dots), S. solfataricus P2 (triangles), and an abiotic control (squares). Pyroglutamate content differentiated significantly between S. acidocaldarius and S. solfataricus (Wilcoxon–Mann–Whitney test including Benjamini-Hochberg correction, ). Values represent the average of four independent cultivations. Error bars represent the standard error between the four experiments.

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