Abstract
In caring for our collection of anaërobic cultures which now numbers 69 strains distributed among 15 clearly recognizable species and 4 strains as yet unidentified, we have observed that certain ones habitually form white crystalline products in the deep brain medium that is used for preserving the stock cultures; namely 3 strains of B. bifermentans, 4 of B. centrosporogenes (a new species shortly to be described for the first time), 1 of B. histolyticus, and especially an unplaced culture, herewith designated No. 106, that resembles B. sporogenes in certain properties but differs in its striking crystal formation. All of these are actively putrefactive anaërobes.
We have failed to observe such crystals in 6 strains of B. Welchii, 3 of B. Novyi, 2 of B. butyricus, 19 serologically homologous strains of B. sporogenes, 5 heterologous strains of B. sporogenes, 2 strains of B. botulinus Type A, 3 of B. botulinus Type B, 7 of Vibrion septique, 7 of B. tetani, 3 of B. putrificus, and 1 each of B. Chauveauii, B. sphenoides, B. tertius, and B. tetanomorphus. Of this list B. sporogenes and B. botulinus are actively putrefactive, B. tetani and B. putrificus less strikingly so.
References to crystals supposed on microscopic grounds to be tyrosine in cultures of putrefactive anaerobes are scattered through the literature, a review of which is reserved for a more detailed report. So far as we are aware, no one else has recovered tyrosin in a state of high purity from a pure culture of any single bacterium.
Our studies to date show that culture No. 106 produces crystals, macro- and microscopically resembling tyrosin, in ground meat, brain, salmon, milk and suspended casein mediums not containing fermentable carbohydrates, i.e., monosaccharides in excess.
Get full access to this article
View all access options for this article.