The Experts below are selected from a list of 538704 Experts worldwide ranked by ideXlab platform
John E Dueber - One of the best experts on this subject based on the ideXlab platform.
-
engineering saccharomyces cerevisiae for co utilization of d galacturonic Acid and d glucose from citrus peel waste
Nature Communications, 2018Co-Authors: Ryan J Protzko, Luke N Latimer, Ze Martinho, Elise De Reus, Tanja Seibert, Philipp J Benz, John E DueberAbstract:Pectin-rich biomasses, such as citrus peel and sugar beet pulp, hold promise as inexpensive feedstocks for microbial fermentations as enzymatic hydrolysis of their component polysaccharides can be accomplished inexpensively to yield high concentrations of fermentable sugars and D-Galacturonic Acid (d-galUA). In this study, we tackle a number of challenges associated with engineering a microbial strain to convert pectin-rich hydrolysates into commodity and specialty chemicals. First, we engineer d-galUA utilization into yeast, Saccharomyces cerevisiae. Second, we identify that the mechanism of d-galUA uptake into yeast is mediated by hexose transporters and that consumption of d-galUA is inhibited by d-glucose. Third, we enable co-utilization of d-galUA and d-glucose by identifying and expressing a heterologous transporter, GatA, from Aspergillus niger. Last, we demonstrate the use of this transporter for production of the platform chemical, meso-galactaric Acid, directly from industrial Navel orange peel waste.
-
identification and characterization of a galacturonic Acid transporter from neurospora crassa and its application for saccharomyces cerevisiae fermentation processes
Biotechnology for Biofuels, 2014Co-Authors: Philipp J Benz, Ryan J Protzko, John E Dueber, Jonas M S Andrich, Stefan Bauer, Chris SomervilleAbstract:Background Pectin-rich agricultural wastes potentially represent favorable feedstocks for the sustainable production of alternative energy and bio-products. Their efficient utilization requires the conversion of all major constituent sugars. The current inability of the popular fermentation host Saccharomyces cerevisiae to metabolize the major pectic monosaccharide D-Galacturonic Acid (D-GalA) significantly hampers these efforts. While it has been reasoned that the optimization of cellular D-GalA uptake will be critical for the engineering of D-GalA utilization in yeast, no dedicated eukaryotic transport protein has been biochemically described. Here we report for the first time such a eukaryotic D-GalA transporter and characterize its functionality in S. cerevisiae.
Zygmunt Sidorczyk - One of the best experts on this subject based on the ideXlab platform.
-
Structure of the O-polysaccharide of Proteus mirabilis CCUG 10705 (OF) containing an amide of D-Galacturonic Acid with L-alanine.
Carbohydrate Research, 2006Co-Authors: Andrei V. Perepelov, Yuriy A Knirel, Alexander S Shashkov, Agnieszka Zabłotni, Zygmunt SidorczykAbstract:Abstract The structure of the O-polysaccharide of Proteus mirabilis CCUG 10705 (OF) was determined by chemical analyses along with one- and two-dimensional 1 H and 13 C NMR spectroscopy. The polysaccharide was found to contain an amide of d -galacturonic Acid with l -alanine and based on the uniqueness of the O-polysaccharide structure and serological data, it was suggested to classify P. mirabilis OF into a new separate Proteus serogroup, O74. A weak cross-reactivity of P. mirabilis OF and P. mirabilis O5 was observed and accounted for by a similarity of their O-repeating units. The following structure of the polysaccharide of P. mirabilis OF was established: Download full-size image
-
Structure and epitope specificity of the O-specific polysaccharide of Proteus penneri strain 12 (ATCC 33519) containing the amide of D-Galacturonic Acid with L-threonine.
European journal of biochemistry, 1995Co-Authors: Zygmunt Sidorczyk, Anna Swierzko, Yuriy A. Knkel, Eugeny V. Vinogradov, Anatoly Ya. Chernyak, Leonid O. Kononov, Maciej Cedzynski, Antoni Rozalski, Wiesław Kaca, Aleksander S. ShashkovAbstract:0-specific polysaccharide was isolated from Proteus penneri strain 12 (ATCC 33519) lipopolysaccharide (LPS) and studied using NMR spectroscopy, including selective spin-decoupling, one-dimensional NOE, two-dimensional homonuclear correlation spectroscopy, I3C,’H heteronuclear correlation spectroscopy and chemical methods (0-deacetylation, Smith degradation, partial Acid hydrolysis followed by borohydride reduction and methylation). The amide of D-gdaCtUrOniC Acid with L-threonine [D-GalA(LThr)] was identified as a constituent of the polysaccharide and the following structure of the tetrasaccharide repeating unit was established:
Peter Richard - One of the best experts on this subject based on the ideXlab platform.
-
Metabolic engineering of the fungal D-galacturonate pathway for L-ascorbic Acid production
Microbial Cell Factories, 2015Co-Authors: Joosu Kuivanen, Merja Penttilä, Peter RichardAbstract:Background Synthetic L-ascorbic Acid (vitamin C) is widely used as a preservative and nutrient in food and pharmaceutical industries. In the current production method, D-glucose is converted to L-ascorbic Acid via several biochemical and chemical steps. The main source of L-ascorbic Acid in human nutrition is plants. Several alternative metabolic pathways for L-ascorbic Acid biosynthesis are known in plants. In one of them, D-Galacturonic Acid is the precursor. D-Galacturonic Acid is also the main monomer in pectin, a plant cell wall polysaccharide. Pectin is abundant in biomass and is readily available from several waste streams from fruit and sugar processing industries. Results In the present work, we engineered the filamentous fungus Aspergillus niger for the conversion of D-Galacturonic Acid to L-ascorbic Acid. In the generated pathway, the native D-galacturonate reductase activity was utilized while the gene coding for the second enzyme in the fungal D-Galacturonic Acid pathway, an L-galactonate consuming dehydratase, was deleted. Two heterologous genes coding for enzymes from the plant L-ascorbic Acid pathway – L-galactono-1,4-lactone lactonase from Euglena gracilis ( EgALase ) and L-galactono-1,4-lactone dehydrogenase from Malpighia glabra ( MgGALDH ) – were introduced into the A. niger strain. Alternatively, an unspecific L-gulono-1,4-lactone lactonase ( smp30 ) from the animal L-ascorbic Acid pathway was introduced in the fungal strain instead of the plant L-galactono-1,4-lactone lactonase. In addition, a strain with the production pathway inducible with D-Galacturonic Acid was generated by using a bidirectional and D-Galacturonic Acid inducible promoter from the fungus. Even though, the lactonase enzyme activity was not observed in the resulting strains, they were capable of producing L-ascorbic Acid from pure D-Galacturonic Acid or pectin-rich biomass in a consolidated bioprocess. Product titers up to 170 mg/l were achieved. Conclusions In the current study, an L-ascorbic Acid pathway using D-Galacturonic Acid as a precursor was introduced to a microorganism for the first time. This is also the first report on an engineered filamentous fungus for L-ascorbic Acid production and a proof-of-concept of consolidated bioprocess for the production.
-
Identification in Agrobacterium tumefaciens of the D-Galacturonic Acid dehydrogenase gene
Applied Microbiology and Biotechnology, 2010Co-Authors: Harry Boer, Hannu Maaheimo, Anu Koivula, Merja Penttilä, Peter RichardAbstract:There are at least three different pathways for the catabolism of d -galacturonate in microorganisms. In the oxidative pathway, which was described in some prokaryotic species, d -galacturonate is first oxidised to meso -galactarate (mucate) by a nicotinamide adenine dinucleotide (NAD)-dependent dehydrogenase (EC 1.1.1.203). In the following steps of the pathway mucate is converted to 2-keto-glutarate. The enzyme activities of this catabolic pathway have been described while the corresponding gene sequences are still unidentified. The d -galacturonate dehydrogenase was purified from Agrobacterium tumefaciens , and the mass of its tryptic peptides was determined using MALDI-TOF mass spectrometry. This enabled the identification of the corresponding gene udh . It codes for a protein with 267 amino Acids having homology to the protein family of NAD(P)-binding Rossmann-fold proteins. The open reading frame was functionally expressed in Saccharomyces cerevisiae . The N-terminally tagged protein was not compromised in its activity and was used after purification for a kinetic characterization. The enzyme was specific for NAD and accepted d -galacturonic Acid and d -glucuronic Acid as substrates with similar affinities. NMR analysis showed that in water solution the substrate d -galacturonic Acid is predominantly in pyranosic form which is converted by the enzyme to 1,4 lactone of galactaric Acid. This lactone seems stable under intracellular conditions and does not spontaneously open to the linear meso -galactaric Acid.
-
D-Galacturonic Acid catabolism in microorganisms and its biotechnological relevance
Applied Microbiology and Biotechnology, 2009Co-Authors: Peter Richard, Satu HilditchAbstract:d -Galacturonic Acid is the main constituent of pectin, a naturally abundant compound. Pectin-rich residues accumulate when sugar is extracted from sugar beet or juices are produced from citrus fruits. It is a cheap raw material but currently mainly used as animal feed. Pectin has the potential to be an important raw material for biotechnological conversions to fuels or chemicals. In this paper, we review the microbial pathways for the catabolism of d- galacturonic Acid that would be relevant for the microbial conversion to useful products.
Andrei V. Perepelov - One of the best experts on this subject based on the ideXlab platform.
-
structure of the o polysaccharide of vibriocholerae o43 containing a new monosaccharide derivative 4 n acetyl l allothreonyl amino 4 6 dideoxy d glucose
Carbohydrate Research, 2011Co-Authors: Andrei V. Perepelov, Yuriy A Knirel, Nina A Kocharova, Pererik Jansson, Andrej WeintraubAbstract:Abstract The O-polysaccharide of Vibrio cholerae O43 was studied using chemical analyses, triflic Acid solvolysis and 2D NMR spectroscopy, including 1 H/ 1 H COSY, TOCSY, NOESY and 1 H/ 13 C gradient-selected HSQC experiments. The following structure of the tetrasaccharide repeating unit of the polysaccharide was established: →3)-β- d -Qui p 4NAcyl-(1→3)-α- d -Gal p NAcA-(1→4)-α- d -Gal p NAc-(1→3)-α- d -Qui p NAc-(1→ where d -QuiNAc stands for 2-acetamido-2,6-dideoxy- d -glucose, d -Qui4NAcyl for 4-( N -acetyl- l -allothreonyl)amino-4,6-dideoxy- d -glucose and d -GalNAcA for 2-acetamido-2-deoxy- d -galacturonic Acid.
-
Structure of the O-polysaccharide of Proteus mirabilis CCUG 10705 (OF) containing an amide of D-Galacturonic Acid with L-alanine.
Carbohydrate Research, 2006Co-Authors: Andrei V. Perepelov, Yuriy A Knirel, Alexander S Shashkov, Agnieszka Zabłotni, Zygmunt SidorczykAbstract:Abstract The structure of the O-polysaccharide of Proteus mirabilis CCUG 10705 (OF) was determined by chemical analyses along with one- and two-dimensional 1 H and 13 C NMR spectroscopy. The polysaccharide was found to contain an amide of d -galacturonic Acid with l -alanine and based on the uniqueness of the O-polysaccharide structure and serological data, it was suggested to classify P. mirabilis OF into a new separate Proteus serogroup, O74. A weak cross-reactivity of P. mirabilis OF and P. mirabilis O5 was observed and accounted for by a similarity of their O-repeating units. The following structure of the polysaccharide of P. mirabilis OF was established: Download full-size image
Yuriy A Knirel - One of the best experts on this subject based on the ideXlab platform.
-
Structure of the O-polysaccharide of Providencia alcalifaciens O25 containing an amide of D-Galacturonic Acid with Nɛ-[(R)-1-carboxyethyl]-L-lysine
Biochemistry (Moscow), 2011Co-Authors: Nina A Kocharova, Yuriy A Knirel, A. S. Shashkov, Olga G. Ovchinnikova, Magdalena Bialczak-kokot, Antoni RozalskiAbstract:An Acidic O-polysaccharide was isolated by mild Acid degradation of the lipopolysaccharide of Providencia alcalifaciens O25 followed by gel-permeation and anion-exchange chromatography. The O-polysaccharide was studied by sugar and methylation analyses along with 1H and 13C NMR spectroscopy, including two-dimensional correlation 1H,13C HMBC, and 1H,1H ROESY experiments both in D2O and, to detect correlations for NH protons, in a 9: 1 H2O/D2O mixture. An amino Acid was isolated from the polysaccharide by Acid hydrolysis and identified as Nɛ-[(R)-1-carboxyethyl]-L-lysine (“alaninolysine”, 2S,8R-alaLys) by determination of the specific optical rotation and 13C NMR spectroscopy, using the authentic synthetic diastereomers 2S,8R-alaLys and 2S,8S-alaLys for comparison. The structure of the branched tetrasaccharide repeating unit of the O-polysaccharide was established.
-
structure of the o polysaccharide of vibriocholerae o43 containing a new monosaccharide derivative 4 n acetyl l allothreonyl amino 4 6 dideoxy d glucose
Carbohydrate Research, 2011Co-Authors: Andrei V. Perepelov, Yuriy A Knirel, Nina A Kocharova, Pererik Jansson, Andrej WeintraubAbstract:Abstract The O-polysaccharide of Vibrio cholerae O43 was studied using chemical analyses, triflic Acid solvolysis and 2D NMR spectroscopy, including 1 H/ 1 H COSY, TOCSY, NOESY and 1 H/ 13 C gradient-selected HSQC experiments. The following structure of the tetrasaccharide repeating unit of the polysaccharide was established: →3)-β- d -Qui p 4NAcyl-(1→3)-α- d -Gal p NAcA-(1→4)-α- d -Gal p NAc-(1→3)-α- d -Qui p NAc-(1→ where d -QuiNAc stands for 2-acetamido-2,6-dideoxy- d -glucose, d -Qui4NAcyl for 4-( N -acetyl- l -allothreonyl)amino-4,6-dideoxy- d -glucose and d -GalNAcA for 2-acetamido-2-deoxy- d -galacturonic Acid.
-
Structure of the O-polysaccharide of Proteus mirabilis CCUG 10705 (OF) containing an amide of D-Galacturonic Acid with L-alanine.
Carbohydrate Research, 2006Co-Authors: Andrei V. Perepelov, Yuriy A Knirel, Alexander S Shashkov, Agnieszka Zabłotni, Zygmunt SidorczykAbstract:Abstract The structure of the O-polysaccharide of Proteus mirabilis CCUG 10705 (OF) was determined by chemical analyses along with one- and two-dimensional 1 H and 13 C NMR spectroscopy. The polysaccharide was found to contain an amide of d -galacturonic Acid with l -alanine and based on the uniqueness of the O-polysaccharide structure and serological data, it was suggested to classify P. mirabilis OF into a new separate Proteus serogroup, O74. A weak cross-reactivity of P. mirabilis OF and P. mirabilis O5 was observed and accounted for by a similarity of their O-repeating units. The following structure of the polysaccharide of P. mirabilis OF was established: Download full-size image
-
Structure of an Acidic polysaccharide from a marine bacterium Pseudoalteromonas distincta KMM 638 containing 5-acetamido-3,5,7,9-tetradeoxy-7- formamido-L-glycero-L-manno-nonulosonic Acid
Carbohydrate Research, 2001Co-Authors: Jimmy Muldoon, Yuriy A Knirel, Svetlana V. Tomshich, Nadezhda A. Komandrova, Lyudmila A Romanenko, Sof'ya N. Senchenkova, Alexander S Shashkov, Angela V. SavageAbstract:Abstract An Acidic polysaccharide was obtained from the lipopolysaccharide of Pseudoalteromonas distincta strain KMM 638, isolated from a marine sponge, and found to contain d -GlcA, d -GalNAc, 2-acetamido-2,6-dideoxy- d -glucose ( d -QuiNAc) and two unusual Acidic amino sugars: 2-acetamido-2-deoxy- d -galacturonic Acid ( d -GalNAcA) and 5-acetamido-3,5,7,9-tetradeoxy-7-formamido- l - glycero - l - manno -nonulosonic Acid (Pse5Ac7Fo, a derivative of pseudaminic Acid). Oligosaccharides were derived from the polysaccharide by partial Acid hydrolysis and mild alkaline degradation and characterised by electrospray ionisation (ESI) MS and 1 H and 13 C NMR spectroscopy. Based on these data and NMR spectroscopic studies of the initial and O-deacetylated polysaccharides, including quaternary carbon detection, 2D COSY, TOCSY, ROESY, H-detected 1 H, 13 C HMQC and HMBC experiments, the following structure of the branched pentasaccharide repeating unit was established: Download full-size image where the degree of O-acetylation of d -Gal p NAcA at position 3 is ∼60%.