Thiamine, thiamin, or vitamin B1, named as the "thio-vitamine" ("sulfur-containing vitamin") is a vitamin of the B complex. First named aneurin for the detrimental neurological effects if not present in the diet, it was eventually assigned the generic descriptor name vitamin B1. Its phosphate derivatives are involved in many cellular processes. The best-characterized form is thiamine pyrophosphate (TPP), a coenzyme in the catabolism of sugars and amino acids.
Thiamine availability in the gut is expected to fluctuate due to various factors, including host genetics, diet, and intestinal adsorption.
Gut microbes that are wholly dependent on thiamine transport, such as members of the genus Alistipes and many members of the bacilli, are likely to be adversely affected during drops in thiamine availability. [PMCID: PMC5613172]