Acidaminococcus gen. n., Acidaminococcus fermentans sp. n., Anaerobic Gram-negative Diplococci Using Amino Acids as the Sole Energy Source for Growth

Abstract

Acidaminococcus gen. n. and the type species Acidaminococcusfermentans sp. n. were described. Amino acids, of which glutamic acid is the most important, could serve as the sole energy source for growth. Acetic and butyric acids and CO2 were produced; propionic acid and hydrogen were not produced. Amino acid media supporting growth and the amino acid and vitamin requirements were described. Glucose was frequently not fermented or was weakly catabolized. Derivative products from glucose autoclaved in media, but not glucose itself, stimulated or were required for growth in amino acid media. A wide range of polyols and carbohydrates were not attacked. Lactate, fumarate, malate, succinate, citrate, and pyruvate were not used as energy sources for growth. Pyruvate completely suppressed growth. Cytochrome oxidase and benzidine reactions were negative; catalase, indole, acetyl methyl carbinol, and H2S were not produced; nitrate and sulfonthalein indicators were not reduced; ammonia was produced; gelatin liquefaction was negative or slow and partial; vancomycin (7.5 ,Ag/ml) was resisted. Acidaminococcus was different from Veillonella in morphology, serology, nutrition, utilization of substrates, and accumulation of products in media supporting growth; Acidaminococcus resembled Peptococcus in utilization of glutamic acid and accumulation of similar products, but the two genera differed in morphology, gram reaction, serology, guanine plus cytosine content of deoxyribonucleic acid, and nutrition. Fuller (6) isolated 49 strains of gram-negative anaerobic cocci from the pig alimentary tract. In some cursory morphological and physiological respects, particularly in their reported inability to ferment carbohydrates, polyols, and lactate, these strains appeared to resemble some Veillonella, as

Location of the Two Genes Encoding Glutaconate Coenzyme A-Transferase at the Beginning of the Hydroxyglutarate Operon in Acidaminococcus fermentans

“…The six (gctA, gctB, gcdA, hgdC, hgdA and hgdB) genes, with a total length of 7.3 kb, all show the same codon preference, indicating that no frame-shifts have occurred during cloning and sequencing. The average G+C content of the sequenced DNA part of A. fermentans (56%) is consistent with the overall G+C content of this organism (56.6%; Rogosa, 1969).…”

“…The DNA sequence between ORFIII and gctA revealed a non-coding intergenic region with an A+T content of 70% over a length of approximately 300 bp (Fig. 3), whereas the average A+T content of A. fermentans is 43.4% (Rogosa, 1969). This finding suggests that the AT-rich region might comprise a RNA-polymerase-binding site controlling the transcription of the gene cluster gctA, gctB, gcdA, hgdC, hgdA and hgdB.…”

“…A. fermentuns ATCC 25085 (Rogosa, 1969) was grown anaerobically on the sodium glutamate/yeast extract medium described earlier (Buckel et al, 1981). E. coli DH5a (Hanahan, 1983) which was used for cloning, sequencing and expression experiments was cultivated aerobically on standard nutrient broth (Merck).…”

Cloning, sequencing and expression of the gene encoding the carboxytransferase subunit of the biotin‐dependent Na+ pump glutaconyl‐CoA decarboxylase from Acidaminococcus fermentans in Escherichia coli

“…A. fermentuns ATCC 2508.5 (Rogosa, 1969) was grown anaerobically on the sodium glutamate yeast extract medium described earlier (Buckel, 1986) in a 100-1 fermenter (Biostat 100 D, Braun Melsungen).…”

Phylogenetic and chemotaxonomic characterization of Acidaminococcus fermentans

“…Both, lnstitut fiir AIIgemeine Mikrobiologie, Christian Albrechts Universitiit, Kiel, FRG. glutamate fermentation in the gastrointestinal tract of homothermic animals [1,2]. Acetic and butyric acid as well as CO 2 and ammonia are the main end products: hydrogen is formed in smaller amounts [3].…”