H. A. Barker

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Two pathways are involved in the fermentation of glutamate to acetate, butyrate, carbon dioxide, and ammonia-the methylaspartate and the hydroxyglutarate pathways which are used by Clostridium tetanomorphum and Peptococcus aerogenes, respectively. Although these pathways give rise to the same products, they are easily distinguished by different labeling(More)
1. The isolation of pure cultures ofMb. Omelianskii has been achieved by the agar shake culture method. The purity of the cultures was established by microscopic examination and by testing for possible contaminants in suitable media under both aerobic and anaerobic conditions. 2. The organism is a thin, unbranched, Gram-variable rod. Motility occurs but is(More)
Clostridium k;luyveri is an anaerobic bacterium which was shown several years ago to convert ethanol to caproic acid (l-3). This unusual process could not be adequately studied at that time because of difficulties in growing the organism. These difficulties have recently been overcome and it is now possible to grow the bacterium in any desired quantity in a(More)
The formation of inflammable gas in nature, especially in swamps and mines, has been known since the earliest times. Already in 1776 Volta examined this phenomenon in some detail and arrived at the conclusion that the gas, which is composed chiefly of methane, owes its origin to the rott ing of vegetable materials. The recognition of the fact tha t the(More)
The isolation of three cobamide coenzymes has been briefly reported (1, 2). Methods used in the assay and purificat.ion of the adenylcobamide coenzyme have been described in some detail (3). This paper describes methods used in the isolation of the benzimidazolylcobamide and 5,6-dimethylbenzimidazolylcobamide coenzymes, both of which have been obtained as(More)
(1) Pure cultures of N. closterium and N. palea have been isolated and used in a manometric study of photosynthesis and respiration in diatoms. (2) The influence of light intensity, temperature, carbon dioxide concentration and culture age upon rate of photosynthesis have been investigated. (3) Photosynthetic and respiratory quotients have been determined(More)
1. A survey has been given of the non-spore-forming methaneproducing organisms on the basis of the rare descriptions scattered throughout the literature. 2. The reasons for the great difficulty of isolating these organisms have been discussed and as a result methods have been developed which make possible the growth of various representatives of this group(More)