scholarly journals Monomethylamine as a Nitrogen Source for a Nonmethylotrophic Bacterium, Agrobacterium tumefaciens

2010 ◽  
Vol 76 (12) ◽  
pp. 4102-4104 ◽  
Author(s):  
Yin Chen ◽  
Kathryn L. McAleer ◽  
J. Colin Murrell
Keyword(s):  
Agrobacterium Tumefaciens ◽  
Carbon Source ◽  
Nitrogen Source ◽  
Sole Nitrogen Source ◽  
Key Enzymes ◽  
Genes Encoding

ABSTRACT Monomethylamine can be used by nonmethylotrophs as a sole nitrogen source but not as a carbon source; however, little is known about the genes and enzymes involved. The γ-glutamylmethylamide/N-methylglutamate pathway for monomethylamine utilization by methylotrophs has recently been resolved. We have identified genes encoding key enzymes of this pathway in nonmethylotrophs (e.g., Agrobacterium tumefaciens) and demonstrated that this pathway is also involved in the utilization of monomethylamine as a nitrogen source by nonmethylotrophs.

scholarly journals Mutants affecting histidine utilization inAspergillus nidulans

1975 ◽  
Vol 25 (2) ◽  
pp. 119-135 ◽  
Author(s):  
Meryl Polkinghorne ◽  
M. J. Hynes
Keyword(s):  
Carbon Source ◽  
Nitrogen Source ◽  
Sole Carbon Source ◽  
Nitrogen Sources ◽  
Limiting Factor ◽  
Sole Nitrogen Source ◽  
Wild Type ◽  
Exogenous Substrate ◽  
Growth Properties ◽  
Type Strains

SUMMARYWild-type strains ofAspergillus nidulansgrow poorly onL-histidine as a sole nitrogen source. The synthesis of the enzyme histidase (EC. 4.3.1.3) appears to be a limiting factor in the growth of the wild type, as strains carrying the mutantareA102 allele have elevated histidase levels and grow strongly on histidine as a sole nitrogen source.L-Histidine is an extremely weak sole carbon source for all strains.Ammonium repression has an important role in the regulation of histidase synthesis and the relief of ammonium repression is dependent on the availability of a good carbon source. The level of histidase synthesis does not respond to the addition of exogenous substrate.Mutants carrying lesions in thesarA orsarB loci (suppressor ofareA102) have been isolated. The growth properties of these mutants on histidine as a sole nitrogen source correlate with the levels of histidase synthesized. Mutation at thesarA andsarB loci also reduces the utilization of a number of other nitrogen sources. The data suggest that these two genes may code for regulatory products involved in nitrogen catabolism. No histidase structural gene mutants were identified and possible explanations of this are discussed.

Utilization of chymotrypsin as a sole carbon and (or) nitrogen source by Escherichia coli

1992 ◽  
Vol 38 (4) ◽  
pp. 290-295 ◽  
Author(s):  
Arthur S. Brecher ◽  
Timothy A. Moehlman ◽  
William D. Hann
Keyword(s):  
Escherichia Coli ◽  
Carbon Source ◽  
Nitrogen Source ◽  
Degradation Products ◽  
Defined Medium ◽  
Host Protein ◽  
Mammalian Host ◽  
Sole Nitrogen Source ◽  
E Coli ◽  
Nitrogen Nutrients

α-Chymotrypsin serves as a sole carbon source, sole nitrogen source, and as sole carbon plus nitrogen source for wild-type Escherichia coli in a totally defined medium. Hence, a mammalian host for E. coli may supply the necessary carbon and nitrogen nutrients for the microorganism. Growth is most rapid when chymotrypsin is a sole nitrogen source,and least rapid with chymotrypsin as a carbon source. The approximate doubling times for E. coli utilizing chymotrypsin as a nitrogen source, carbon plus nitrogen source, and carbon source are 1.6, 4.6, and 11.3 h, respectively. The activity of the residual enzyme in the culture supernates falls off asymptotically over the course of time, as followed by cleavage of glutaryl-L-phenylalanine-p-nitroanilide. Chymotrypsin hydrolyzes succinyl-L-ala-L-ala-L-ala-p-nitroanilide, the elastase substrate, to some extent. Peptidases do not appear to be secreted that hydrolyze such model substrates as benzoyl-DL-arginine-p-nitroanilide, the tryptic and cathepsin B substrate, L-leucine-p-nitroanilide, the leucine aminopeptidase substrate, or L-lysine-p-nitroanilide, the aminopeptidase B substrate. Growth of E. coli is generally directly related to the loss of chymotryptic activity in the medium. Hence, autolysis of chymotrypsin, i.e., self-degradation, is an important factor for the availability of degradation products of the enzyme to the bacterium for growth purposes. Accordingly, the degradation of a host protein by autolysis presents an opportunity for E. coli to survive during periods of host nutritional crisis by utilization of the degradation peptides that are produced during autolysis. Key words: chymotrypsin, Escherichia coli, growth, nutrition, peptide source.

scholarly journals The Cryptic Plasmid of Agrobacterium tumefaciens Cointegrates with the Ti Plasmid and Cooperates for Opine Degradation

1998 ◽  
Vol 11 (7) ◽  
pp. 583-591 ◽  
Author(s):  
Valérie Vaudequin-Dransart ◽  
Annik Petit ◽  
W. Scott Chilton ◽  
Yves Dessaux
Keyword(s):  
Agrobacterium Tumefaciens ◽  
Nitrogen Source ◽  
Recipient Strain ◽  
Ti Plasmid ◽  
Cryptic Plasmid ◽  
Physiological Traits ◽  
Sole Nitrogen Source ◽  
Catabolic Plasmid

We crossed the Agrobacterium tumefaciens chrysanthemum strain ANT4, which harbors four plasmids, with the plasmid-free recipient C58.00RS. Transconjugants degrading the Amadori-opines chrysopine and deoxy-fructo-syl-oxo-proline (dfop) harbored the Ti plasmid of ANT4, termed pAtANT4b. Upon transfer to the recipient strain C58.00RS, pAtANT4b (pTiANT4) and pANT4a (the largest of the four plasmids of ANT4) could cointegrate. The cointegration of the two plasmids occurs at various places of the pTiANT4, a feature that may affect several functions of the Ti plasmid (e.g., opine degradation). Transcon-jugants utilizing the opine deoxy-fructosyl-glutamine (dfg) always harbored the large pAtANT4a. Other Agrobacterium strains, including nonpathogenic strains such as C58C1, naturally degraded dfg. Remarkably, strain C58C1 carries a large cryptic plasmid termed pAtC58 that also encodes dfg degradation. A screening of physiological traits additionally revealed that this plasmid allows utilization of octopine as sole nitrogen source after mutation. All these results demonstrate that the larger plasmid of A. tumefaciens is a catabolic plasmid and that both the “cryptic” plasmid and Ti plasmid cooperate for opine degradation.

scholarly journals Transport and Catabolism of Carbohydrates by Neisseria meningitidis

2016 ◽  
Vol 26 (5) ◽  
pp. 320-332 ◽  
Author(s):  
Meriem Derkaoui ◽  
Ana Antunes ◽  
Jamila Nait Abdallah ◽  
Sandrine Poncet ◽  
Alain Mazé ◽  
...  
Keyword(s):  
Carbon Source ◽  
Transgenic Mice ◽  
Neisseria Meningitidis ◽  
Pentose Phosphate Pathway ◽  
Sole Carbon Source ◽  
Minimal Medium ◽  
Pentose Phosphate ◽  
Key Enzymes ◽  
The Real ◽  
Genes Encoding

We identified the genes encoding the proteins for the transport of glucose and maltose in <i>Neisseria meningitidis</i> strain 2C4-3. A mutant deleted for <i>NMV_1892</i><i>(glcP)</i> no longer grew on glucose and deletion of <i>NMV_0424</i><i>(malY)</i> prevented the utilization of maltose. We also purified and characterized glucokinase and α-phosphoglucomutase, which catalyze early catabolic steps of the two carbohydrates. <i>N. meningitidis</i> catabolizes the two carbohydrates either via the Entner-Doudoroff (ED) pathway or the pentose phosphate pathway, thereby forming glyceraldehyde-3-P and either pyruvate or fructose-6-P, respectively. We purified and characterized several key enzymes of the two pathways. The genes required for the transformation of glucose into gluconate-6-P and its further catabolism via the ED pathway are organized in two adjacent operons. <i>N. meningitidis</i> also contains genes encoding proteins which exhibit similarity to the gluconate transporter <i>(NMV_2230)</i> and gluconate kinase <i>(NMV_2231)</i> of Enterobacteriaceae and Firmicutes. However, gluconate might not be the real substrate of <i>NMV_2230</i> because <i>N. meningitidi</i>s was not able to grow on gluconate as the sole carbon source. Surprisingly, deletion of <i>NMV_2230</i> stimulated growth in minimal medium in the presence and absence of glucose and drastically slowed the clearance of <i>N. meningitidis</i> cells from transgenic mice after intraperitoneal challenge.

PRODUCTION OF CYTASES ACTIVE ON BARLEY GUM BY BACTERIA OF THE GENUS BACILLUS

1953 ◽  
Vol 31 (1) ◽  
pp. 28-32 ◽  
Author(s):  
A. C. Blackwood
Keyword(s):  
Bacillus Subtilis ◽  
Enzymatic Activity ◽  
Nitrogen Source ◽  
Freeze Drying ◽  
Shake Flask ◽  
Sole Nitrogen Source ◽  
Genus Bacillus ◽  
Original Activity ◽  
Bacterial Cultures ◽  
Bacillus Genus

One hundred and fourteen bacterial cultures representing most of the species in the Bacillus genus were tested for the production of extracellular barley gum cytase. Assays were made on shake-flask cultures grown on a medium containing glucose and yeast extract. Although all the organisms had some enzymatic activity, certain strains of Bacillus subtilis gave the best yields of cytase. On a medium with asparagine as the sole nitrogen source even higher yields were obtained. The crude cytase preparations were stable and after freeze-drying most of the original activity remained.

Studies on the Biological Characteristics of Termitomyces Albuminosus Hypha

2013 ◽  
Vol 709 ◽  
pp. 810-813 ◽  
Author(s):  
Xiong Ya ◽  
Min Jie Li
Keyword(s):  
Growth Factors ◽  
Carbon Source ◽  
Nitrogen Source ◽  
Biological Characteristics ◽  
Edible Fungi ◽  
Growth Environment ◽  
Wild Edible Fungi ◽  
Development And Utilization

Termitomyces albuminosus is a kind of local distinctive wild edible fungi in southwest of China. It is delicious, rich in nutrition and has high development and utilization value, but owing to the restrictions of growth environment, it can not be cultivated artificially. This article mainly studied on the biological characteristics of Termitomyces albuminosus Hypha, and found out the optimal carbon source, nitrogen source, growth factors and the C/N ratio that are suitable for the growth of Hypha of Termitomyces albuminosus .

scholarly journals Production of Feruloyl Esterase from Aspergillus niger by Solid-State Fermentation on Different Carbon Sources

2011 ◽  
Vol 2011 ◽  
pp. 1-4 ◽  
Author(s):  
Shiyi Ou ◽  
Jing Zhang ◽  
Yong Wang ◽  
Ning Zhang
Keyword(s):  
Carbon Source ◽  
Nitrogen Source ◽  
Wheat Bran ◽  
Cell Walls ◽  
Carbon Sources ◽  
Feruloyl Esterase ◽  
Plant Cell Walls ◽  
Optimal Conditions ◽  
Carbon And Nitrogen ◽  
Maize Bran

A mixture of wheat bran with maize bran as a carbon source and addition of (NH4)SO4 as nitrogen source was found to significantly increase production of feruloyl esterase (FAE) enzyme compared with wheat bran as a sole carbon and nitrogen source. The optimal conditions in conical flasks were carbon source (30 g) to water 1 : 1, maize bran to wheat bran 1 : 2, (NH4)SO4 1.2 g and MgSO4 70 mg. Under these conditions, FAE activity was 7.68 mU/g. The FAE activity on the mixed carbon sources showed, high activity against the plant cell walls contained in the cultures.

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