The enzymic formation of hydrogen sulphide by certain heterotrophic bacteria

Abstract

NONE of the numerous investigators who have studied the formation of hydrogen sulphide by bacteria has thoroughly analysed the relation between the organic sulphur-containing substrate employed and the formation of this compound. Furthermore, the failure to eliminate bacterial multiplication may have obscured to some extent the simple formation of hydrogen sulphide.Sasaki and Otsuka [1912] found that most of a large number of bacteria studied by them formed hydrogen sulphide when cultivated in Frankel's artificial medium to which either cystine or sulphur had been added. Certain of the strains investigated formed this gas from thiosulphate, only a few formed it from sulphite, and none produced it from taurine or from sulphate. Burger [1914] found that the bacteria which he studied formed hydrogen sulphide from cystine but not from taurine. Tanner [1917], employing Frankel's medium, studied a very large number of cultures and found that most of these formed hydrogen sulphide from peptone and from cystine, some from thiosulphate and thiourea, and that none of the strains formed this gas from 2-thiohydantoin, sulphite or sulphate. Almy and James [1926] showed that, when P. vulgaris was grown in a peptone solution containing added cystine, all the sulphur of this amino-acid could be recovered as hydrogen sulphide. Hydrogen sulphide was formed in cultures of this organism under both anaerobic and aerobic conditions. Tarr [1933] showed that washed cells of P. vulgaris decomposed cystine completely under anaerobic conditions, with the formation of two molecules each of hydrogen sulphide, ammonia, acetic and formic acids.In the present investigation it has been shown that the process of hydrogen sulphide formation by washed cells of certain heterotrophic bacteria is enzymic in nature, a relatively high degree of specificity existing between the structure of the organic molecule attacked and the production of hydrogen sulphide. A study of certain well-known bacterial species has been made in order to determine the distribution of the enzyme concerned; and one factor which stimulates its formation in the bacterial cell has been found. EXPERIMENTAL.Many of the substances used, viz. glutathione (oxidised and reduced forms), cystine, cysteine hydrochloride, glycylcysteine, N-acetylcysteine, N-acetylcysteine, methyl and propyl esters, S-ethylcysteine, S-benzylcysteine, methionine, 1 1851 Exhibition

Microbiological Fractionation of Sulphur Isotopes

“…Fractionation during mineralization of organic sulphur The cleavage of the sulphydryl group of cysteine by Proteus vulgaris (Tarr, 1933(Tarr, , 1934 resulted in an enrichment of the lighter isotope in the hydrogen sulphide with a maximum 834S-5.1 %, , (Table 5 ) . …”

Thiosulfate Reduction in Salmonella enterica Is Driven by the Proton Motive Force

“…The thiosulfate produced is then available as a respiratory substrate for colonic bacteria. The ability of certain enteric pathogens to produce sulfide from thiosulfate has been know for almost one hundred years (69) and is the basis of some commercial tests used for strain differentiation in clinical diagnostic laboratories. Genera of enteric bacteria that typically reduce thiosulfate include Salmonella, Proteus, Citrobacter, and Edwardsiella.…”

Synthesis ofl-Cysteine and Its Analogues by Intact Cells Containing Cysteine Desulfhydrase

“…The enzyme responsible for this conversion was first demonstrated in cell extracts from Proteus vulgaris by Tarr 7 ) and subsequently from Escherichia coli by Fromageot and Desunuelle. 8 ) The enzyme responsible for this conversion is called cysteine desulfhydrase.…”