Malonate and Krebs Cycle Intermediates Utilization in the Presence of other Carbon Sources by Rhizobium japonicum and Soybean Bacteroids

1982 ◽  
Vol 37 (10) ◽  
pp. 921-926 ◽  
Author(s):  
Dietrich Werner ◽  
Walburga Dittrich ◽  
Heidemarie Thierfelder
Keyword(s):  
Sole Carbon Source ◽  
Carbon Sources ◽  
Krebs Cycle ◽  
Living Cells ◽  
The Other ◽  
Rhizobium Japonicum ◽  
Free Living ◽  
Low Concentrations ◽  
Substrate Saturation ◽  
Krebs Cycle Intermediates

Abstract Free living cells of Rhizobium japonicum 61-A-101 and bacteroids from Glycine max var. Mandarin infected with the same strain utilized malonate with a substrate saturation greater than 10-2 mol/l. At low concentrations of malonate (10-5 mol/1) the free living cells were significantly more active in utilizing malonate than bacteroids. In bacteroids two substrate saturation ranges were found, one between 3 x 10-4mol/l and 10-3 mol/l, the other at more than 10-2 mol/l. Utilization of malonate was not affected by 10 to 100 times larger concentrations of either arabinose or xylose. 10-3 mol/l succinate inhibited the utilization of malonate (10-4 mol/l) completely in bacteroids, and by 90% in free living cells. Succinate utilization (10-4 mol/1) was reduced in those cells exposed to 100 times higher malonate concentration only by 20-30% . Utilization and incorporation of pyruvate and 2-oxoglutarate into bacteroids was also only slightly affected by 100 times larger malonate concentration. Citrate utilization by bacteroids however was reduced by more than 70%. The rate of endoxidation of malonate as sole carbon source (14CO2 production from [2-14C] malonic acid)was about 1.5 μmol · h-1 • mg protein-1 and about half the rate with Pseudomonas putida and 70% o f the rate with Pseudomonas fluorescens under the same conditions (pH 6.0, 28 °C).

Differentiation of Rhizobium japonicum, I. Enzymatic Comparison of Nitrogenase Repressed and Derepressed Free Living Cells and of Bacteroids

1978 ◽  
Vol 33 (3-4) ◽  
pp. 245-252 ◽  
Author(s):  
D. Werner ◽  
R. Stripf
Keyword(s):  
Gas Phase ◽  
Liquid Culture ◽  
Nitrogenase Activity ◽  
Living Cells ◽  
Maximum Activity ◽  
Rhizobium Japonicum ◽  
Free Living ◽  
Low Concentrations ◽  
Specific Activities ◽  
Japonicum Strain

Derepressed free living cells of Rhizobium japonicum strain 61-A-101 with leucine as single nitrogen source develop a maximum nitrogenase activity of 180 nmol C2H4 · mg protein -1·h-1 in liquid culture under 2% O2 in the gas phase. Only 10% of this activity is found with no oxygen in the gas phase during a 90 min incubation period. The maximum activity under 2% oxygen in the gas phase is unaffected by addition of 1 -100 mM NH4* and by addition of low concentrations of glutamine (0.36 - 1.44 mᴍ).Specific activities of alanine dehydrogenase (E.C. 1.4.1.1.) aspartate aminotransferase (E.C. 2.6.1.1.) and, with much lower activities, of GOGAT (E.C. 1.4.1.13) in nitrogenase active free living cells are more similar to bacteroids than to nitrogenase repressed free living cells from liquid culture. The activities in nitrogenase repressed cells were about 50% lower. Glutamine synthetase (E.C. 6.3.1.2.) activity in bacteroids and in nitrogenase active cells were also similar, but only about 25 - 30% of that found in nitrogenase repressed Rhizobium japonicum cells.

scholarly journals YvcK of Bacillus subtilis is required for a normal cell shape and for growth on Krebs cycle intermediates and substrates of the pentose phosphate pathway

Microbiology ◽  
2005 ◽  
Vol 151 (11) ◽  
pp. 3777-3791 ◽  
Author(s):  
Boris Görke ◽  
Elodie Foulquier ◽  
Anne Galinier
Keyword(s):  
Bacillus Subtilis ◽  
Pentose Phosphate Pathway ◽  
Carbon Metabolism ◽  
Carbon Sources ◽  
Krebs Cycle ◽  
Normal Growth ◽  
Central Carbon Metabolism ◽  
Pentose Phosphate ◽  
Homologous Protein ◽  
Krebs Cycle Intermediates

The HPr-like protein Crh has so far been detected only in the bacillus group of bacteria. In Bacillus subtilis, its gene is part of an operon composed of six ORFs, three of which exhibit strong similarity to genes of unknown function present in many bacteria. The promoter of the operon was determined and found to be constitutively active. A deletion analysis revealed that gene yvcK, encoded by this operon, is essential for growth on Krebs cycle intermediates and on carbon sources metabolized via the pentose phosphate pathway. In addition, cells lacking YvcK acquired media-dependent filamentous or L-shape-like aberrant morphologies. The presence of high magnesium concentrations restored normal growth and cell morphology. Furthermore, suppressor mutants cured from these growth defects appeared spontaneously with a high frequency. Such suppressing mutations were identified in a transposon mutagenesis screen and found to reside in seven different loci. Two of them mapped in genes of central carbon metabolism, including zwf, which encodes glucose-6-phosphate dehydrogenase and cggR, the product of which regulates the synthesis of glyceraldehyde-3-phosphate dehydrogenase. All these results suggest that YvcK has an important role in carbon metabolism, probably in gluconeogenesis required for the synthesis of cell wall precursor molecules. Interestingly, the Escherichia coli homologous protein, YbhK, can substitute for YvcK in B. subtilis, suggesting that the two proteins have been functionally conserved in these different bacteria.

scholarly journals Symbiotic Bradyrhizobium japonicum Reduces N2O Surrounding the Soybean Root System via Nitrous Oxide Reductase

2006 ◽  
Vol 72 (4) ◽  
pp. 2526-2532 ◽  
Author(s):  
Reiko Sameshima-Saito ◽  
Kaori Chiba ◽  
Junta Hirayama ◽  
Manabu Itakura ◽  
Hisayuki Mitsui ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
Root System ◽  
Bradyrhizobium Japonicum ◽  
Reductase Activity ◽  
Ambient Air ◽  
Living Cells ◽  
Nitrous Oxide Reductase ◽  
Free Living ◽  
Low Concentrations ◽  
Soybean Roots

ABSTRACT N2O reductase activity in soybean nodules formed with Bradyrhizobium japonicum was evaluated from N2O uptake and conversion of 15N-N2O into 15N-N2. Free-living cells of USDA110 showed N2O reductase activity, whereas a nosZ mutant did not. Complementation of the nosZ mutant with two cosmids containing the nosRZDFYLX genes of B. japonicum USDA110 restored the N2O reductase activity. When detached soybean nodules formed with USDA110 were fed with 15N-N2O, they rapidly emitted 15N-N2 outside the nodules at a ratio of 98.5% of 15N-N2O uptake, but nodules inoculated with the nosZ mutant did not. Surprisingly, N2O uptake by soybean roots nodulated with USDA110 was observed even in ambient air containing a low concentration of N2O (0.34 ppm). These results indicate that the conversion of N2O to N2 depends exclusively on the respiratory N2O reductase and that soybean roots nodulated with B. japonicum carrying the nos genes are able to remove very low concentrations of N2O.

On the DNA Content of the Bacteroids of Rhizobium japonicum

1979 ◽  
Vol 34 (9-10) ◽  
pp. 793-796
Author(s):  
John Wilcockson ◽  
Dietrich Werner
Keyword(s):  
Stationary Phase ◽  
Dna Content ◽  
Living Cells ◽  
Rhizobium Japonicum ◽  
Published Data ◽  
Free Living ◽  
A Value ◽  
Soybean Plants ◽  
Japonicum Strain

Abstract The DNA content of bacteroids from large nodules of soybean plants infected with Rhizobium japonicum strain 61 -A -101 was found to be 1.20 × 10-14 g per cell. Bacteroids from smaller nodules had slightly less DNA as did the stationary phase, free-living cells; both giving a value of 0.92 × 10-14 g per cell. In comparing these data with those of other workers it was found that there is little evidence to support suggestions that bacteroids possess anything less than a full genetic complement of DNA and that some misinterpretation of older published data has occurred.

scholarly journals Evaluation of EPS Application in Microbial Consortia Growing in Aqueous Co-Contaminated Systems: The Trend to Natural Attenuation

2008 ◽  
Vol 2 (1) ◽  
pp. 176-182 ◽  
Author(s):  
P.S.O. Martins ◽  
N.F. Almeida ◽  
R.G.S. Costa ◽  
A.P. Franco ◽  
M.F. Vieira ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Natural Attenuation ◽  
Carbon Sources ◽  
Inhibitory Effect ◽  
Aqueous System ◽  
The Other ◽  
Microbial Consortia ◽  
Low Concentrations ◽  
Negative Effect ◽  
Potential Use

The needing of a bacterial extracellular polymeric substance (EPS) application in bioremediation of an aqueous system containing glucose and/or gasoline and/or heavy metals (Cd2+, Zn2+ and Cu2+) by two different microbial consortia was studied. At the low concentrations (1.00 ppm of each metal), it was observed an inhibitory effect on the metabolism of the “consortium 1”, as well as the application of EPS has improved the cellular growing in media containing glucose and/or gasoline as carbon sources, indicating that using this substance decreases the negative effect caused by the presence of heavy metals. In the other hand, the application of small concentrations of EPS was evaluated, and results show that a little increase in this substance concentration leads to an improvement of 39 % in cellular growing of the “consortium 2”, indicating the potential use of the EPS in a system with gasoline and metals. Once many microorganisms can produce this kind of substance during cultivation, our results show that a system with low concentrations of hydrocarbons and metals could be susceptible to natural attenuation, without human intervention in the environment, especially if the process is conducted in a larger period of time.

Cold-sensitive mutant with defective growth at 5 °C from a psychrotrophic bacterium

1980 ◽  
Vol 26 (1) ◽  
pp. 1-6 ◽  
Author(s):  
W. D. Murray ◽  
W. E. Inniss
Keyword(s):  
Atpase Activity ◽  
Specific Activity ◽  
Carbon Sources ◽  
Krebs Cycle ◽  
Effect Of Temperature ◽  
Restrictive Temperature ◽  
Permissive Temperature ◽  
Wild Type ◽  
Cold Sensitive ◽  
Krebs Cycle Intermediates

A cold-sensitive (CS) mutant of the psychrotroph, Bacillus psychrophilus, was obtained by N-methyl-N′-nitro-N-nitrosoguanidine mutagenization and penicillin counterselection. In the presence of citrate, the wild type grew well at both 5 and 20 °C whereas the CS mutant grew well at 20 °C (the permissive temperature) but, at 5 °C (the restrictive temperature), grew at a reduced rate for two to three generations followed by a complete plateau in growth. Upon return of the CS mutant to 20 °C, after a delay of about 40 h, growth resumed at the appropriate rate. The CS mutant exhibited growth rates similar to parental rates on a wide variety of carbon sources at 5 °C, but when Krebs cycle intermediates were used as substrates and in the presence of an equimolar amount of citrate, the typical cold-sensitive growth pattern occurred. Comparison of oxidative phosphorylation in the parent and CS mutant indicated that no phosphorylation occurred at 5 °C in the CS mutant during the plateau in growth. Examination of the effect of temperature on ATPase activity showed that at 5 °C the specific activity of ATPase isolated from the CS mutant grown at 5 °C was 15-fold less than the ATPases isolated from wild-type cells grown at either 5 or 20 °C and 10.5-fold lower than ATPase from CS mutant cells grown at 20 °C. The large reduction in CS mutant ATPase activity at 5 °C appears to be at least partly due to an effect on synthesis since citrate did not inhibit preformed ATPase.

scholarly journals Metabolic Outcomes of Anaplerotic Dodecanedioic Acid Supplementation in Very Long Chain Acyl-CoA Dehydrogenase (VLCAD) Deficient Fibroblasts

Metabolites ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 538
Author(s):  
Igor Radzikh ◽  
Erica Fatica ◽  
Jillian Kodger ◽  
Rohan Shah ◽  
Ryan Pearce ◽  
...  
Keyword(s):  
Alternative Energy ◽  
Carbon Sources ◽  
Krebs Cycle ◽  
Dicarboxylic Acids ◽  
High Energy ◽  
Glycolytic Flux ◽  
Chain Acyl ◽  
Krebs Cycle Intermediates ◽  
Dodecanedioic Acid ◽  
Long Chain

Very long-chain acyl-CoA dehydrogenase deficiency (VLCADD, OMIM 609575) is associated with energy deficiency and mitochondrial dysfunction and may lead to rhabdomyolysis and cardiomyopathy. Under physiological conditions, there is a fine balance between the utilization of different carbon nutrients to maintain the Krebs cycle. The maintenance of steady pools of Krebs cycle intermediates is critical formitochondrial energy homeostasis especially in high-energy demanding organs such as muscle and heart. Even-chain dicarboxylic acids are established as alternative energy carbon sources that replenish the Krebs cycle by bypassing a defective β-oxidation pathway. Despite this, even-chain dicarboxylic acids are eliminated in the urine of VLCAD-affected individuals. In this study, we explore dodecanedioic acid (C12; DODA) supplementation and investigate its metabolic effect on Krebs cycle intermediates, glucose uptake, and acylcarnitine profiles in VLCAD-deficient fibroblasts. Our findings indicate that DODA supplementation replenishes the Krebs cycle by increasing the succinate pool, attenuates glycolytic flux, and reduces levels of toxic very long-chain acylcarnitines.

Alanine Dehydrogenase from Bacteroids and Free Living Cells of Rhizobium japonicum

1982 ◽  
Vol 37 (10) ◽  
pp. 927-936 ◽  
Author(s):  
Peter Müller ◽  
Dietrich Werner
Keyword(s):  
Molecular Weight ◽  
Specific Activity ◽  
Nitrogenase Activity ◽  
Ammonium Assimilation ◽  
Living Cells ◽  
Total Cell ◽  
Rhizobium Japonicum ◽  
Free Living ◽  
Alanine Dehydrogenase ◽  
Cell Extracts

Abstract Alanine dehydrogenase (E.C. 1.4.1.1.) from nitrogenase repressed free living cells of Rhizobium japonicum 61-A-101 was purified 370 fold to a specific activity o f 30.4 (μmol pyruvate · min-1 · mg protein-1. The same enzyme from effective bacteroids from nodules of Glycine max var. Mandarin, infected with the same strain was purified 150 fold to a specific activity of 35 units. The enzyme from both preparations was identical in the molecular weight of about 168 kD with four identical subunits of 42 kD. The alanine dehydrogenase is, therefore, different from the same enzyme from Bacillus subtilis (molecular weight 228 kD) and from Anabaena cylindrica (molec­ ular weight 270 kD). The Kᴍ data for the enzyme from Rhizobium japonicum are: 4.7 mmol/l for NH+4 0.68 mmol/l for pyruvate and 44 μmol/l for NADH. Specific activity of the enzyme in total cell extracts from eight other strains of Rhizobium japonicum (3 effective strains, 5 ineffective strains) was only 20 to 30% o f the activity with strain 61-A-101. No correlation between alanine dehydrogenase activity and nitrogenase activity in these other eight strains was observed. The function of alanine dehydrogenase in Rhizobium japonicum in ammonium assimilation and cell wall differentiation is discussed.

Effect of C6-Volatiles on Bioluminescent Plant Pathogens

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 557d-557
Author(s):  
Jennifer Warr ◽  
Fenny Dane ◽  
Bob Ebel
Keyword(s):  
Biological Activity ◽  
Bacterial Growth ◽  
Xanthomonas Campestris ◽  
Plant Pathogens ◽  
Genetically Engineered ◽  
The Other ◽  
Computer Assisted ◽  
Signal Molecules ◽  
Low Concentrations

C6 volatile compounds are known to be produced by the plant upon pathogen attack or other stress-related events. The biological activity of many of these substances is poorly understood, but some might produce signal molecules important in host–pathogen interactions. In this research we explored the possibility that lipid-derived C6 volatiles have a direct effect on bacterial plant pathogens. To this purpose we used a unique tool, a bacterium genetically engineered to bioluminesce. Light-producing genes from a fish-associated bacterium were introduced into Xanthomonas campestris pv. campestris, enabling nondestructive detection of bacteria in vitro and in the plant with special computer-assisted camera equipment. The effects of different C6 volatiles (trans-2 hexanal, trans-2 hexen-1-ol and cis-3 hexenol) on growth of bioluminescent Xanthomonas campestris were investigated. Different volatile concentrations were used. Treatment with trans-2 hexanal appeared bactericidal at low concentrations (1% and 10%), while treatments with the other volatiles were not inhibitive to bacterial growth. The implications of these results with respect to practical use of trans-2 hexanal in pathogen susceptible and resistant plants will be discussed.

Capture of conspecific planktonic larvae by the suspension-feeding gastropod Crepipatella peruviana: association between adult and larval size

2021 ◽  
Vol 87 (1) ◽  
Author(s):  
G A Rivera-Figueroa ◽  
J A Büchner-Miranda ◽  
L P Salas-Yanquin ◽  
J A Montory ◽  
V M Cubillos ◽  
...  
Keyword(s):  
Laboratory Experiments ◽  
Larval Mortality ◽  
Feeding Preference ◽  
The Other ◽  
Suspension Feeding ◽  
Adult Size ◽  
Free Living ◽  
Larval Size ◽  
Suspension Feeders ◽  
Planktonic Larvae

ABSTRACT Free-living, planktonic larvae can be vulnerable to capture and ingestion by adult suspension-feeders. This is particularly the case for larvae that settle gregariously in benthic environments where suspension-feeders occur at high densities. Larvae of gregarious suspension-feeding species are at particularly high risk, as adults of their own species often serve as cues for metamorphosis. We conducted laboratory experiments to assess the extent to which adults of the suspension-feeding caenogastropod Crepipatella peruviana would capture and ingest their own larvae. Experiments were conducted with adults of different sizes, with larvae of different ages and sizes, and in the presence or absence of phytoplankton. Adults captured larvae in all experiments. The presence of microalgae in the water did not influence the extent of larval capture. On average, 39% of larvae were captured during the 3-h feeding periods, regardless of adult size. However, up to 34% of the larvae that were captured on the gill were later discarded as pseudofaeces; the other 64% were ingested. The extent of capture by adults was not related to adult size, or to larval size and, thus, to larval age. Our results suggest that the filtration of congeneric larvae by adult C. peruviana is a result of accidental capture rather than a deliberate feeding preference. Such ingestion could, however, still be an important source of larval mortality, especially when the advanced larvae of this species are searching for a suitable substrate for metamorphosis.

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