%0 Journal Article %A Weeks, O. B. %A Beck, S. M. %T Nutrition of Flavobacterium aquatile Strain Taylor and a Microbiological Assay for Thiamine %D 1960 %J Microbiology, %V 23 %N 2 %P 217-229 %@ 1465-2080 %R https://doi.org/10.1099/00221287-23-2-217 %I Microbiology Society, %X SUMMARY Flavobacterium aquaiile strain Taylor grew readily in a medium containing (%, w/v); trypticase, 0·5; glucose, 0·5; K2HPO4, 0·05; KH2PO4, 0·05; MgSO4.7H2O, 0·02; supplemental thiamine. Growth was proportional to the thiamine-HCl content in the range 1·80 mμg./10 ml. medium. Larger quantities of thiamine did not increase growth. Maximum growth responses at all concentrations of thiamine were obtained after 48 hr. incubation at 30° when the cultures were shaken during incubation. The response of F. aquatile to thiamine gives a basis for a microbiological assay. Of the compounds tested only thiamine pyrophosphate and acetylthiamine replaced thiamine. None of the other vitamins, or various purines, pyrimidines, nucleosides, or miscellaneous compounds tested except certain carbohydrates, altered the response to thiamine. Maltose or ribose (0·:5 %, w/v) stimulated F. aqua-tile in the range 0–5 mμg. thiamine/10 ml. At greater concentrations of thiamine, and in the presence of glucose, slight growth inhibitions were caused by maltose and ribose. Sodium chloride at concentrations greater than 0·:05 m retarded growth generally and therefore the response to thiamine was modified. None of the interfering compounds appeared to invalidate the use of the bacterium as an assay organism for thiamine. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-23-2-217