Regulation of methanol metabolism in the facultative methylotroph Nocardia sp. 239 during growth on mixed substrates in batch- and continuous cultures

In natural and man-made environments microorganisms often grow in the presence of a diversity of functionally similar substrates. The pattern of utilization of these mixed substrates is generally dependent upon their concentration. When substrates are present in high (not growth-limiting) concentrations, sequential utilization and diauxic growth is often observed and the substrate that supports the highest growth rate is utilized preferentially from the mixture. When the substrate concentrations are growth-limiting, simultaneous utilization of the various compounds present in the mixture appears to be the general response. Recent studies on mixed substrate utilization in both batch and continuous cultures have thrown light on the strategies of the control mechanisms that, in microbes, govern the utilization of the various substrates. But perhaps more importantly these studies have indicated the possible significance of mixed substrate utilization in microbial competition in nutrient-limited natural ecosystems.

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Methanol as a fermentation substrate for the production of phenylalanine, tyrosine and tryptophan by the facultative methylotroph Nocardia sp. 239

Antonie van Leeuwenhoek ◽

10.1007/bf00404550 ◽

1985 ◽

Vol 51 (5-6) ◽

pp. 566-567 ◽

Cited By ~ 1

Author(s):

L. de Boer ◽

W. Clement ◽

L. Dijkhuizen ◽

W. Harder

Keyword(s):

Facultative Methylotroph ◽

Nocardia Sp ◽

Fermentation Substrate

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Microscopic investigations of novel intracellular bodies of a Nocardia SP

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100169511 ◽

1994 ◽

Vol 52 ◽

pp. 356-357

Author(s):

J. L. Stites

Keyword(s):

Uranyl Acetate ◽

Electron Microscopic ◽

En Bloc ◽

Ribonucleic Acids ◽

Transmission Electron ◽

Nocardia Sp ◽

Internal Constitution ◽

Membrane Bound ◽

Molecular Components ◽

Protein Rich

A Nocardia sp.was found during an initial transmission electron microscopic (TEM) examination to have unusual intracellular bodies (ICB's) which do not appear to have been described previously in the literature. Most intracellular structures within bacteria have been classified as storage granules, a product of membrane invagination (i.e. mesosomes), or vacuoles. In bacteria there are no known intracellular membrane-bound organelles, and all internal membranes are invaginations of the unit membrane. Several microscopic-level examinations of the Nocardia sp. ICB's were initiated in order to determine their overall structure, classification, and internal constitution.Different TEM staining procedures were performed to determine possible molecular components of the ICB. In all of the staining protocols the ICB's showed a lack of electron density similar to the cell wall. Because the ICB's showed no affinity to any stain, it appeared they do not have strong positive charge (phosphotungstic acid), are not protein rich (en bloc uranyl acetate), lack glycogen and are not phosphate or sulphur rich (lead citrate), nor do they contain lipids or ribonucleic acids (osmium tetroxide).

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Faculty Opinions recommendation of Continuous cultures of fused cells secreting antibody of predefined specificity.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.12104956.13253055 ◽

2011 ◽

Author(s):

Patrick C Wilson

Keyword(s):

Continuous Cultures

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Anaerobic Semi-Continuous Culture Biodegradation of Dichlorophenols Containing an Ortho Chlorine

Water Quality Research Journal ◽

10.2166/wqrj.1987.033 ◽

1987 ◽

Vol 22 (3) ◽

pp. 427-436 ◽

Cited By ~ 6

Author(s):

S.E. Hrudey ◽

E. Knettig ◽

P.M. Fedorak ◽

S.A. Daignault

Keyword(s):

Activated Carbon ◽

Continuous Culture ◽

Chlorine Atom ◽

Degradation Process ◽

Anaerobic Sludge ◽

Continuous Cultures ◽

Complete Mineralization

Abstract Rapid and preferential dechlorination of the ortho chlorine from 2,6-, 2,4- and 2,3- dichlorophenol substrates was observed in semi-continuous cultures inoculated with 50% unacclimated anaerobic sludge. The rate of further dechlorination depended on the position of the second chlorine atom. The dechlorination rates for the second chlorine ranked ortho > para > meta. Complete mineralization to methane was only observed in cultures fed 2,6-dichlorophenol. Addition of activated carbon to the anaerobic cultures showed some benefit to the degradation process.

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