Cxxix. Synthesis of Vitamin B1 by Intestinal Bacteria of the Rat

MANY types of micro-organisms have been tested by various workers for their ability to synthesize "vitamin B" (=complex). In such studies the organisms were grown in various nutrient media and the " vitamin B " was detected by its growth-promoting action or by curative tests on experimental animals such as the rat, the mouse or the pigeon. Thus "vitamin B " has been reported to have been produced by Pfeiffer's bacillus [Damon, 1923], Mycobacterium smegmatis, Mycobact. phlei and Mycobact. moeleri [Damon, 1924], Monila candida [Hoet et al. 1924], B. vulgatus [Scheunert & Schieblich, 1923], various types of Torula, Oospora, Actinomyces and Eubacteriales [Sunderlin & Werkman, 1928], B. ellenbachiensis and B. prodigiosum [Schieblich, 1931], B. lactis aerogenes and Vibrio alcaligenes [Schieblich, 1933]. On the other hand, the following microorganisms (among others) have been found to produce no vitamin: Lactobacillus bulgaricus and Amylomucor B [Wollman, 1921; Wollman & Vagliano, 1922], Bact. lactisacidi, B. mycoides, B. subtilis and Micrococcus agilis [Slanetz, 1923], Bact. coli [Cooper, 1914], the tubercle bacillus [Cunningham, 1924]. Considering the above results together, it seems reasonable to believe that different types of bacteria may vary in their ability to synthesize " vitamin B ". This view receives direct support from the experiments of Schieblich [1931], who showed that there was a well marked difference in the extent of the synthesis of "vitamin B" by various bacteria. Thus, when grown in a suitable culture medium, B. vulgatus was found to produce large amounts of the vitamin B complex, B. mycoides smaller amounts and B. mesentericus very small quantities only. These conclusions were based on growth tests on rats. An examination of the literature also shows that studies of the synthesis of "vitamin B" by a specific organism have produced somewhat contradictory results. To take one example, Bact. coli was reported to be unable to synthesize "vitamin B", by Cooper [1914], Damon [1921], Eijkman et al. [1922], and Weill et al. [1922], while positive results were claimed by Kuroya & Hosoya [1923] and by Sunderlin & Werkman [1928]. Of the various causes which may account for this lack of agreement the following are perhaps the most important: (1) the use of different methods for detecting the presence of the vitamin, (2) the administration ofinsufficientamountsof micro-organisms forthe feeding test and (3) the use of different culture media by the various workers. Most of the work mentioned above dealt probably with the bacterial synthesis of the "vitamin B" complex as a whole rather than with its separate components. More recently, however, the synthesis of vitamin B1 by B. vulgatus has been reported by Guha [1932]. Various other investigators have presented evidence which suggested that vitamin B1 is synthesized in the intestinal tract of the rat [Roscoe, 1931; Guerrant et al. 1935; Wbipple & Church, 1935; Leong, 1937].