scholarly journals Modulation of Glucose Transport Causes Preferential Utilization of Aromatic Compounds in Pseudomonas putida CSV86

2007 ◽  
Vol 189 (21) ◽  
pp. 7556-7562 ◽  
Author(s):  
Aditya Basu ◽  
Rahul Shrivastava ◽  
Bhakti Basu ◽  
Shree K. Apte ◽  
Prashant S. Phale
Keyword(s):  
Organic Acids ◽  
Pseudomonas Putida ◽  
Glucose Transport ◽  
Aromatic Compounds ◽  
Carbon Sources ◽  
Mass Spectrometry Analysis ◽  
Periplasmic Space ◽  
Two Dimensional Gel Electrophoresis ◽  
Spectrometry Analysis ◽  
Glucose Binding

ABSTRACT Pseudomonas putida CSV86 utilizes aromatic compounds in preference to glucose and coutilizes aromatics and organic acids. Protein analysis of cells grown on different carbon sources, either alone or in combination, revealed that a 43-kDa periplasmic-space protein was induced by glucose and repressed by aromatics and succinate. Two-dimensional gel electrophoresis and liquid chromatography-tandem mass spectrometry analysis identified this protein as closely resembling the sugar ABC transporter of Pseudomonas putida KT2440. A partially purified 43-kDa protein showed glucose binding activity and was specific for glucose. The results demonstrate that the aromatic- and organic acid-mediated repression of a periplasmic-space glucose binding protein and consequent inhibition of glucose transport are responsible for this strain's ability to utilize aromatics and organic acids in preference to glucose.

scholarly journals Repression of the glucose-inducible outer-membrane protein OprB during utilization of aromatic compounds and organic acids in Pseudomonas putida CSV86

Microbiology ◽  
2011 ◽  
Vol 157 (5) ◽  
pp. 1531-1540 ◽  
Author(s):  
Rahul Shrivastava ◽  
Bhakti Basu ◽  
Ashwini Godbole ◽  
M. K. Mathew ◽  
Shree K. Apte ◽  
...  
Keyword(s):  
Membrane Protein ◽  
Organic Acids ◽  
Pseudomonas Putida ◽  
Outer Membrane ◽  
Outer Membrane Protein ◽  
Aromatic Compounds ◽  
Mass Spectrometry Analysis ◽  
Binding Studies ◽  
Spectrometry Analysis ◽  
Glucose Binding

Pseudomonas putida CSV86 shows preferential utilization of aromatic compounds over glucose. Protein analysis and [14C]glucose-binding studies of the outer membrane fraction of cells grown on different carbon sources revealed a 40 kDa protein that was transcriptionally induced by glucose and repressed by aromatics and succinate. Based on 2D gel electrophoresis and liquid chromatography-tandem mass spectrometry analysis, the 40 kDa protein closely resembled the porin B of P. putida KT2440 and carbohydrate-selective porin OprB of various Pseudomonas strains. The purified native protein (i) was estimated to be a homotrimer of 125 kDa with a subunit molecular mass of 40 kDa, (ii) displayed heat modifiability of electrophoretic mobility, (iii) showed channel conductance of 166 pS in 1 M KCl, (iv) permeated various sugars (mono-, di- and tri-saccharides), organic acids, amino acids and aromatic compounds, and (v) harboured a glucose-specific and saturable binding site with a dissociation constant of 1.3 µM. These results identify the glucose-inducible outer-membrane protein of P. putida CSV86 as a carbohydrate-selective protein OprB. Besides modulation of intracellular glucose-metabolizing enzymes and specific glucose-binding periplasmic space protein, the repression of OprB by aromatics and organic acids, even in the presence of glucose, also contributes significantly to the strain’s ability to utilize aromatics and organic acids over glucose.

scholarly journals Understanding Mechanisms of Salinity Tolerance in Barley by Proteomic and Biochemical Analysis of Near-Isogenic Lines

2020 ◽  
Vol 21 (4) ◽  
pp. 1516 ◽  
Author(s):  
Juan Zhu ◽  
Yun Fan ◽  
Sergey Shabala ◽  
Chengdao Li ◽  
Chao Lv ◽  
...  
Keyword(s):  
Salinity Tolerance ◽  
Crop Production ◽  
Biochemical Analysis ◽  
Mass Spectrometry Analysis ◽  
Near Isogenic Lines ◽  
Ros Scavenging ◽  
Hordeum Vulgare L ◽  
Two Dimensional Gel Electrophoresis ◽  
Spectrometry Analysis ◽  
Isogenic Lines

Salt stress is one of the major environmental factors impairing crop production. In our previous study, we identified a major QTL for salinity tolerance on chromosome 2H on barley (Hordeum vulgare L.). For further investigation of the mechanisms responsible for this QTL, two pairs of near-isogenic lines (NILs) differing in this QTL were developed. Sensitive NILs (N33 and N53) showed more severe damage after exposure to 300 mM NaCl than tolerant ones (T46 and T66). Both tolerant NILs maintained significantly lower Na+ content in leaves and much higher K+ content in the roots than sensitive lines under salt conditions, thus indicating the presence of a more optimal Na+/K+ ratio in plant tissues. Salinity stress caused significant accumulation of H2O2, MDA, and proline in salinity-sensitive NILs, and a greater enhancement in antioxidant enzymatic activities at one specific time or tissues in tolerant lines. One pair of NILs (N33 and T46) were used for proteomic studies using two-dimensional gel electrophoresis. A total of 53 and 51 differentially expressed proteins were identified through tandem mass spectrometry analysis in the leaves and roots, respectively. Proteins which are associated with photosynthesis, reactive oxygen species (ROS) scavenging, and ATP synthase were found to be specifically upregulated in the tolerant NIL. Proteins identified in this study can serve as a useful resource with which to explore novel candidate genes for salinity tolerance in barley.

scholarly journals Proteomic Analysis of Liver from Human Lipoprotein(a) Transgenic Mice Shows an Oxidative Stress and Lipid Export Response

2018 ◽  
Vol 2018 ◽  
pp. 1-11
Author(s):  
Euan J. Rodger ◽  
Carolyn M. Porteous ◽  
Gregory T. Jones ◽  
Michael Legge ◽  
Torsten Kleffmann ◽  
...  
Keyword(s):  
Human Liver ◽  
Density Lipoprotein ◽  
Bioinformatic Analysis ◽  
Liver Cells ◽  
Mass Spectrometry Analysis ◽  
Two Dimensional Gel Electrophoresis ◽  
Lipoprotein A ◽  
Spectrometry Analysis ◽  
Human Liver Cells ◽  
Proteomic Approach

Background. Mouse models of hypercholesterolaemia have been used to identify arterial proteins involved in atherosclerosis. As the liver is extremely sensitive to dyslipidemia, one might expect major changes in the abundance of liver proteins in these models even before atherosclerosis develops. Methods. Lipid levels were measured and a proteomic approach was used to quantify proteins in the livers of mice with an elevated low-density lipoprotein (LDL) and the presence of lipoprotein(a) [Lp(a)] but no atherosclerosis. Results. The livers of Lp(a) mice showed an increased triglyceride but reduced phospholipid and oxidised lipid content. Two-dimensional gel electrophoresis and mass spectrometry analysis identified 24 liver proteins with significantly increased abundance in Lp(a) mice (P<0.05). A bioinformatic analysis of the 24 proteins showed the major effect was that of an enhanced antioxidant and lipid efflux response with significant increases in antioxidant (Park7, Gpx1, Prdx6, and Sod1) and lipid metabolism proteins (Fabp4, Acaa2, apoA4, and ApoA1). Interestingly, human liver cells treated with Lp(a) showed significant increases in Gpx1 and Prdx6 but not Sod1 or Park7. Conclusions. The presence of human LDL and Lp(a) in mice promotes an enhanced flux of lipids into the liver which elicits an antioxidant and lipid export response before the onset of atherosclerosis. The antioxidant response can be reproduced in human liver cells treated with Lp(a).

scholarly journals The Pseudomonas putida Crc Global Regulator Controls the Expression of Genes from Several Chromosomal Catabolic Pathways for Aromatic Compounds

2004 ◽  
Vol 186 (5) ◽  
pp. 1337-1344 ◽  
Author(s):  
Gracia Morales ◽  
Juan Francisco Linares ◽  
Ana Beloso ◽  
Juan Pablo Albar ◽  
José Luis Martínez ◽  
...  
Keyword(s):  
Pseudomonas Putida ◽  
Carbon Metabolism ◽  
Aromatic Compounds ◽  
Carbon Sources ◽  
Signal Transduction Pathway ◽  
Catabolic Repression ◽  
Catabolic Pathways ◽  
Expression Of Genes ◽  
Proteome Profile

ABSTRACT The Crc protein is involved in the repression of several catabolic pathways for the assimilation of some sugars, nitrogenated compounds, and hydrocarbons in Pseudomonas putida and Pseudomonas aeruginosa when other preferred carbon sources are present in the culture medium (catabolic repression). Crc appears to be a component of a signal transduction pathway modulating carbon metabolism in pseudomonads, although its mode of action is unknown. To better understand the role of Crc, the proteome profile of two otherwise isogenic P. putida strains containing either a wild-type or an inactivated crc allele was compared. The results showed that Crc is involved in the catabolic repression of the hpd and hmgA genes from the homogentisate pathway, one of the central catabolic pathways for aromatic compounds that is used to assimilate intermediates derived from the oxidation of phenylalanine, tyrosine, and several aromatic hydrocarbons. This led us to analyze whether Crc also regulates the expression of the other central catabolic pathways for aromatic compounds present in P. putida. It was found that genes required to assimilate benzoate through the catechol pathway (benA and catBCA) and 4-OH-benzoate through the protocatechuate pathway (pobA and pcaHG) are also negatively modulated by Crc. However, the pathway for phenylacetate appeared to be unaffected by Crc. These results expand the influence of Crc to pathways used to assimilate several aromatic compounds, which highlights its importance as a master regulator of carbon metabolism in P. putida.

scholarly journals Nitrobenzoates and Aminobenzoates Are Chemoattractants for Pseudomonas Strains

2004 ◽  
Vol 70 (1) ◽  
pp. 285-292 ◽  
Author(s):  
Rebecca E. Parales
Keyword(s):  
Pseudomonas Putida ◽  
Aromatic Compounds ◽  
Carbon Sources ◽  
Chemotactic Response ◽  
Aromatic Acids ◽  
Wide Range ◽  
Catechol 1,2 Dioxygenase ◽  
Sense And Respond ◽  
Chemotaxis System ◽  
Broad Specificity

ABSTRACT Three Pseudomonas strains were tested for the ability to sense and respond to nitrobenzoate and aminobenzoate isomers in chemotaxis assays. Pseudomonas putida PRS2000, a strain that grows on benzoate and 4-hydroxybenzoate by using the β-ketoadipate pathway, has a well-characterized β-ketoadipate-inducible chemotactic response to aromatic acids. PRS2000 was chemotactic to 3- and 4-nitrobenzoate and all three isomers of aminobenzoate when grown under conditions that induce the benzoate chemotactic response. P. putida TW3 and Pseudomonas sp. strain 4NT grow on 4-nitrotoluene and 4-nitrobenzoate by using the ortho (β-ketoadipate) and meta pathways, respectively, to complete the degradation of protocatechuate derived from 4-nitrotoluene and 4-nitrobenzoate. However, based on results of catechol 1,2-dioxygenase and catechol 2,3-dioxygenase assays, both strains were found to use the β-ketoadipate pathway for the degradation of benzoate. Both strains were chemotactic to benzoate, 3- and 4-nitrobenzoate, and all three aminobenzoate isomers after growth with benzoate but not succinate. Strain TW3 was chemotactic to the same set of aromatic compounds after growth with 4-nitrotoluene or 4-nitrobenzoate. In contrast, strain 4NT did not respond to any aromatic acids when grown with 4-nitrotoluene or 4-nitrobenzoate, apparently because these substrates are not metabolized to the inducer (β-ketoadipate) of the chemotaxis system. The results suggest that strains TW3 and 4NT have a β-ketoadipate-inducible chemotaxis system that responds to a wide range of aromatic acids and is quite similar to that present in PRS2000. The broad specificity of this chemotaxis system works as an advantage in strains TW3 and 4NT because it functions to detect diverse carbon sources, including 4-nitrobenzoate.

scholarly journals Adaptation of Pseudomonas sp. Strain 7-6 to Quaternary Ammonium Compounds and Their Degradation via Dual Pathways

2007 ◽  
Vol 73 (6) ◽  
pp. 1797-1802 ◽  
Author(s):  
Shinji Takenaka ◽  
Takashi Tonoki ◽  
Kazuya Taira ◽  
Shuichiro Murakami ◽  
Kenji Aoki
Keyword(s):  
Lauric Acid ◽  
Quaternary Ammonium ◽  
Carbon Sources ◽  
Nitrogen Sources ◽  
Mass Spectrometry Analysis ◽  
Gas Chromatography Mass Spectrometry ◽  
Continuous Exposure ◽  
Active Sludge ◽  
Spectrometry Analysis ◽  
Ammonium Compounds

ABSTRACT Pseudomonas sp. strain 7-6, isolated from active sludge obtained from a wastewater facility, utilized a quaternary ammonium surfactant, n-dodecyltrimethylammonium chloride (DTAC), as its sole carbon, nitrogen, and energy source. When initially grown in the presence of 10 mM DTAC medium, the isolate was unable to degrade DTAC. The strain was cultivated in gradually increasing concentrations of the surfactant until continuous exposure led to high tolerance and biodegradation of the compound. Based on the identification of five metabolites by gas chromatography-mass spectrometry analysis, two possible pathways for DTAC metabolism were proposed. In pathway 1, DTAC is converted to lauric acid via n-dodecanal with the release of trimethylamine; in pathway 2, DTAC is converted to lauric acid via n-dodecyldimethylamine and then n-dodecanal with the release of dimethylamine. Among the identified metabolites, the strain precultivated on DTAC medium could utilize n-dodecanal and lauric acid as sole carbon sources and trimethylamine and dimethylamine as sole nitrogen sources, but it could not efficiently utilize n-dodecyldimethylamine. These results indicated pathway 1 is the main pathway for the degradation of DTAC.

scholarly journals Host engineering for improved valerolactam production in Pseudomonas putida

2019 ◽  
Author(s):  
Mitchell G. Thompson ◽  
Luis E. Valencia ◽  
Jacquelyn M. Blake-Hedges ◽  
Pablo Cruz-Morales ◽  
Alexandria E. Velasquez ◽  
...  
Keyword(s):  
Metabolic Engineering ◽  
Carbon Source ◽  
Pseudomonas Putida ◽  
Aromatic Compounds ◽  
Sole Carbon Source ◽  
Carbon Sources ◽  
Shotgun Proteomics ◽  
Rich Media ◽  
Amide Hydrolase

ABSTRACTPseudomonas putida is a promising bacterial chassis for metabolic engineering given its ability to metabolize a wide array of carbon sources, especially aromatic compounds derived from lignin. However, this omnivorous metabolism can also be a hindrance when it can naturally metabolize products produced from engineered pathways. Herein we show that P. putida is able to use valerolactam as a sole carbon source, as well as degrade caprolactam. Lactams represent important nylon precursors, and are produced in quantities exceeding one million tons per year[1]. To better understand this metabolism we use a combination of Random Barcode Transposon Sequencing (RB-TnSeq) and shotgun proteomics to identify the oplBA locus as the likely responsible amide hydrolase that initiates valerolactam catabolism. Deletion of the oplBA genes prevented P. putida from growing on valerolactam, prevented the degradation of valerolactam in rich media, and dramatically reduced caprolactam degradation under the same conditions. Deletion of oplBA, as well as pathways that compete for precursors L-lysine or 5-aminovalerate, increased the titer of valerolactam from undetectable after 48 hours of production to ~90 mg/L. This work may serve as a template to rapidly eliminate undesirable metabolism in non-model hosts in future metabolic engineering efforts.

Sign in / Sign up

Export Citation Format

Share Document