scholarly journals Degradation of 2,4,6-Trichlorophenol by Phanerochaete chrysosporium: Involvement of Reductive Dechlorination

1998 ◽  
Vol 180 (19) ◽  
pp. 5159-5164 ◽  
Author(s):  
G. Vijay Bhasker Reddy ◽  
Maarten D. Sollewijn Gelpke ◽  
Michael H. Gold
Keyword(s):  
Phanerochaete Chrysosporium ◽  
Reductive Dechlorination ◽  
Oxidation Products ◽  
Ring Cleavage ◽  
Fungal Metabolites ◽  
Subsequent Degradation ◽  
Metabolic Conditions ◽  
The Common ◽  
Dechlorination Reaction

ABSTRACT Under secondary metabolic conditions, the lignin-degrading basidiomycete Phanerochaete chrysosporium mineralizes 2,4,6-trichlorophenol. The pathway for the degradation of 2,4,6-trichlorophenol has been elucidated by the characterization of fungal metabolites and oxidation products generated by purified lignin peroxidase (LiP) and manganese peroxidase (MnP). The multistep pathway is initiated by a LiP- or MnP-catalyzed oxidative dechlorination reaction to produce 2,6-dichloro-1,4-benzoquinone. The quinone is reduced to 2,6-dichloro-1,4-dihydroxybenzene, which is reductively dechlorinated to yield 2-chloro-1,4-dihydroxybenzene. The latter is degraded further by one of two parallel pathways: it either undergoes further reductive dechlorination to yield 1,4-hydroquinone, which isortho-hydroxylated to produce 1,2,4-trihydroxybenzene, or is hydroxylated to yield 5-chloro-1,2,4-trihydroxybenzene, which is reductively dechlorinated to produce the common key metabolite 1,2,4-trihydroxybenzene. Presumably, the latter is ring cleaved with subsequent degradation to CO2. In this pathway, the chlorine at C-4 is oxidatively dechlorinated, whereas the other chlorines are removed by a reductive process in which chlorine is replaced by hydrogen. Apparently, all three chlorine atoms are removed prior to ring cleavage. To our knowledge, this is the first reported example of aromatic reductive dechlorination by a eukaryote.

Intradiol Aromatic Ring Cleavage in a Dioxygenase Model System

1981 ◽  
Vol 36 (10) ◽  
pp. 1324-1330 ◽  
Author(s):  
Dennis G. Brown ◽  
William J. Hughes
Keyword(s):  
Oxygen Consumption ◽  
Model System ◽  
Oxidation Products ◽  
Ring Cleavage ◽  
Secondary Oxidation ◽  
Isomeric Mixture ◽  
Aromatic Ring Cleavage ◽  
Phenanthroline Ligand ◽  
Kinetics Of

Abstract Dioxygenase Model, Copper, Catechol The complex (3-n-nonylcatecholato)(1,10-phenanthroline)copper(II) reacts with molecular oxygen to give an isomeric mixture of 2-n-nonylmuconic acid and several secondary oxidation products. The catecholato ligand is oxidatively cleaved in an intradiol fashion reminescent of the reactions catalyzed by intradiol aromatic dioxygenases. The 1,10-phenanthroline ligand can be quantitatively recovered and is not oxidized. In addition to characterization of oxidation products, the kinetics of oxygen consumption have been analyzed. The rate law for oxygen uptake is -d[O2]/dt = k[O2] [copper]2 .

scholarly journals Synthesis and analytical characterization of all N–N-coupled, dimeric oxidation products of α-tocopheramine: hydrazo-, azo-, and azoxy-tocopherol

2021 ◽  
Vol 152 (10) ◽  
pp. 1231-1239
Author(s):  
Anjan Patel ◽  
Thomas Rosenau
Keyword(s):  
Aqueous Media ◽  
Analytical Data ◽  
Oxidation Products ◽  
Reaction Systems ◽  
Unknown Structure ◽  
Dimerization Product ◽  
The Common ◽  
First Time ◽  
By Products

AbstractTocopherols are a mixture of antioxidants which are commonly referred to as vitamin E. Tocopheramines differ from tocopherols by an amino function in lieu of the phenolic OH group. They are potent antioxidants which are used in biomedical scenarios as well as stabilizers for polymers against aging. While in aqueous media α-tocopheramine is mainly oxidized to α-tocopherylquinone and N-oxidized by-products, oxidation in apolar media or in polymeric matrices mainly leads to dimeric compounds of hitherto unknown structure. In the present study, we synthesized the whole array of N,N-dimerization product of α-tocopheramine, including the hydrazo, azo, and azoxy derivatives for the first time, and provided comprehensive analytical data as well as general protocols to access the compounds in straightforward syntheses. These results can now be used to identify the common oxidation by-products of α -tocopheramine in different reaction systems. Graphic abstract

Isolation and characterization of oleochemical compounds from watermelon seed

2020 ◽  
Vol 10 (4) ◽  
pp. 79-82
Author(s):  
Madhubhushan M ◽  
Seshaiah S ◽  
Chandrudu J ◽  
Sagar R ◽  
Akila CR
Keyword(s):  
Cutting Tool ◽  
Citrullus Lanatus ◽  
Fatty Esters ◽  
Mineral Oils ◽  
Light Yellow ◽  
Isolation And Characterization ◽  
The Common ◽  
Set Up ◽  
Natural Gradation

The common watermelon item (Citrullus lanatus) seeds were gained from castoffs verdant nourishments for use by decorating, sun ventilation and pulverizing. Light yellow-toned oil was gotten by dissolvable withdrawal using oil atmosphere and the going with traits were gotten using oil ether: pH, refractive rundown, thickness, dissolvable miscibility, coagulating temperature, fire nature, express gravity, streak point and warmth of consuming. With a shallow level of unsaturation, stepped level of smoothness, and proximity of raised degree of the sensible proportion of free unsaturated fats. The low assessment of the solidifying temperature of the oil offered a hint that the oil can be managed in various areas paying little heed to the qualification in temperature. The following level of linoleic destructive of the oil offers a hint of natural gradation of solidarity. Fatty esters are increasing expanding significance as a biodegradable swap for mineral oils. In some request regions, for example, cutting tool oil, gearbox, pressure-driven oils, and greases for raw petroleum creation, the oleochemical items are set up. Nonetheless, certain particular wellsprings of fatty esters are hitherto to be abused for this comparative reason. This exploration subsequently tests into one of the less used wellsprings of fatty esters in watermelon. The oil from the kernels demonstrations a top-notch yield presents significant utilitarian gatherings for change and thus was utilized to set up an assortment of oleochemicals which demonstrated excellence materials in contrast with the routinely utilized oils feed frameworks for oleochemicals after portrayal. The photopolymers acquired indicated piercing vinyl protons for consistent polymerize.

Reason as an Idea

2017 ◽  
Author(s):  
Michael LeBuffe
Keyword(s):  
The Common ◽  
Rational Knowledge ◽  
Human Kind

Spinoza’s characterization of ideas of reason in Ethics 2 makes reason distinctive both psychologically and epistemologically. Psychologically, ideas of reason are frequently present to mind and, as a result, powerful influences on human belief and action; a notable class of ideas of reason, the common notions, are always present to mind. Within such ideas we always regard certain properties to be present in the objects of our experience. Epistemologically, ideas of reason are a distinctively human kind of knowledge, where we cannot immediately know the essences of singular things, as on many views gods or angels might. Instead, in the first instance, rational knowledge is knowledge of properties of things in experience. From such knowledge, Spinoza argues, we can also come to further knowledge by means of processes, and it is these processes that closely resemble what many readers today will recognize as reasoning.

Characterization of Non-volatile Oxidation Products Formed from Triolein in a Model Study at Frying Temperature

2021 ◽  
Vol 69 (11) ◽  
pp. 3466-3478
Author(s):  
Sílvia Petronilho ◽  
Bruna Neves ◽  
Tânia Melo ◽  
Sara Oliveira ◽  
Eliana Alves ◽  
...  
Keyword(s):  
Oxidation Products ◽  
Frying Temperature ◽  
Model Study ◽  
Volatile Oxidation Products

scholarly journals Subtype Characterization and Zoonotic Potential of Cryptosporidium felis in Cats in Guangdong and Shanghai, China

Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 89
Author(s):  
Jiayu Li ◽  
Fuxian Yang ◽  
Ruobing Liang ◽  
Sheng Guo ◽  
Yaqiong Guo ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Phylogenetic Analysis ◽  
Genetic Characterization ◽  
Zoonotic Potential ◽  
Common Occurrence ◽  
High Genetic Diversity ◽  
Gp60 Gene ◽  
The Common ◽  
Subtyping Tool

Cryptosporidiumfelis is an important cause of feline and human cryptosporidiosis. However, the transmission of this pathogen between humans and cats remains controversial, partially due to a lack of genetic characterization of isolates from cats. The present study was conducted to examine the genetic diversity of C. felis in cats in China and to assess their potential zoonotic transmission. A newly developed subtyping tool based on a sequence analysis of the 60-kDa glycoprotein (gp60) gene was employed to identify the subtypes of 30 cat-derived C. felis isolates from Guangdong and Shanghai. Altogether, 20 C. felis isolates were successfully subtyped. The results of the sequence alignment showed a high genetic diversity, with 13 novel subtypes and 2 known subtypes of the XIXa subtype family being identified. The known subtypes were previously detected in humans, while some of the subtypes formed well-supported subclusters with human-derived subtypes from other countries in a phylogenetic analysis of the gp60 sequences. The results of this study confirmed the high genetic diversity of the XIXa subtype family of C. felis. The common occurrence of this subtype family in both humans and cats suggests that there could be cross-species transmission of C. felis.

scholarly journals Genetic characterization at the species and symbiovar level of indigenous rhizobial isolates nodulating Phaseolus vulgaris in Greece

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Evdoxia Efstathiadou ◽  
Georgia Ntatsi ◽  
Dimitrios Savvas ◽  
Anastasia P. Tampakaki
Keyword(s):  
Phaseolus Vulgaris ◽  
Common Bean ◽  
Phylogenetic Affiliation ◽  
Rhizobial Inoculation ◽  
Rhizobial Species ◽  
The Common ◽  
First Time ◽  
Of Greece ◽  
Rhizobial Isolates

AbstractPhaseolus vulgaris (L.), commonly known as bean or common bean, is considered a promiscuous legume host since it forms nodules with diverse rhizobial species and symbiovars. Most of the common bean nodulating rhizobia are mainly affiliated to the genus Rhizobium, though strains belonging to Ensifer, Pararhizobium, Mesorhizobium, Bradyrhizobium, and Burkholderia have also been reported. This is the first report on the characterization of bean-nodulating rhizobia at the species and symbiovar level in Greece. The goals of this research were to isolate and characterize rhizobia nodulating local common bean genotypes grown in five different edaphoclimatic regions of Greece with no rhizobial inoculation history. The genetic diversity of the rhizobial isolates was assessed by BOX-PCR and the phylogenetic affiliation was assessed by multilocus sequence analysis (MLSA) of housekeeping and symbiosis-related genes. A total of fifty fast-growing rhizobial strains were isolated and representative isolates with distinct BOX-PCR fingerpriniting patterns were subjected to phylogenetic analysis. The strains were closely related to R. anhuiense, R. azibense, R. hidalgonense, R. sophoriradicis, and to a putative new genospecies which is provisionally named as Rhizobium sp. I. Most strains belonged to symbiovar phaseoli carrying the α-, γ-a and γ-b alleles of nodC gene, while some of them belonged to symbiovar gallicum. To the best of our knowledge, it is the first time that strains assigned to R. sophoriradicis and harbored the γ-b allele were found in European soils. All strains were able to re-nodulate their original host, indicating that they are true microsymbionts of common bean.

scholarly journals Hemolysis in the spleen drives erythrocyte turnover

Blood ◽  
2020 ◽  
Author(s):  
Thomas robert leon Klei ◽  
Jill Jasmine Dalimot ◽  
Benjamin Nota ◽  
Martijn Veldthuis ◽  
Erik Mul ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Matrix Proteins ◽  
Human Spleen ◽  
Erythrocyte Adhesion ◽  
Subsequent Degradation ◽  
Macrophage Subpopulations ◽  
Senescent Erythrocytes ◽  
Red Pulp

Red pulp macrophages of the spleen mediate turnover of billions of senescent erythrocytes per day. However, the molecular mechanisms involved in sequestration of senescent erythrocytes, their recognition and their subsequent degradation by red pulp macrophages remain unclear. In this study we provide evidence that the splenic environment is of substantial importance in facilitating erythrocyte turnover through induction of hemolysis. Upon isolating human spleen red pulp macrophages we noted a substantial lack of macrophages that were in the process of phagocytosing intact erythrocytes. Detailed characterization of erythrocyte and macrophage subpopulations from human spleen tissue led to the identification of erythrocytes that are devoid of hemoglobin, so-called erythrocyte ghosts. By in vivo imaging and transfusion experiments we further confirmed that senescent erythrocytes that are retained in the spleen are subject to hemolysis. Additionally, we show that erythrocyte adhesion molecules, which are specifically activated on aged erythrocytes, cause senescent erythrocytes to interact with extracellular matrix proteins that are exposed within the splenic architecture. Such adhesion molecule-driven retention of senescent erythrocytes, under low shear conditions, was found to result in steady shrinkage of the cell and ultimately resulted in hemolysis. In contrast to intact senescent erythrocytes, the remnant erythrocyte ghost shells were prone to recognition and breakdown by red pulp macrophages. These data identify hemolysis as a key event in the turnover of senescent erythrocytes, which alters our current understanding of how erythrocyte degradation is regulated.

Detection and characterization of Leptospira spp. in dogs diagnosed with kidney and/or liver disease in Selangor, Malaysia

2021 ◽  
pp. 104063872110245
Author(s):  
Sabri A. Rahman ◽  
Kuan H. Khor ◽  
Siti Khairani-Bejo ◽  
Seng F. Lau ◽  
Mazlina Mazlan ◽  
...  
Keyword(s):  
Liver Disease ◽  
Mortality Rate ◽  
Direct Detection ◽  
Bacterial Disease ◽  
Pathogenic Leptospira ◽  
Wide Range ◽  
Leptospira Spp ◽  
Rrna Sequencing ◽  
The Common

Leptospirosis is a serious bacterial disease that affects both humans and animals. A wide range of symptoms have been described in humans; the disease in dogs is commonly associated with kidney and/or liver disease. In Malaysia, information about the common serovars infecting dogs is limited. Therefore, we investigated the occurrences of leptospirosis in 124 pet dogs diagnosed with kidney and/or liver disease. Blood, urine, abdominal effusion, and/or kidney and liver were collected from the dogs. Based on microscopic agglutination testing, 53 of 124 (42.7%) dogs were seropositive for leptospiral exposure. Sera were frequently positive to serovars Bataviae ( n = 12), Javanica ( n = 10), and Icterohaemorrhagiae ( n = 10). Direct detection using PCR showed that 42 of 124 (33.9%) of the whole blood and 36 of 113 (31.9%) urine samples were positive for pathogenic Leptospira spp. By PCR, 2 of 23 (9.1%) kidney and 2 of 23 (9.1%) liver were positive for pathogenic Leptospira spp. Abdominal effusion from 4 dogs were PCR-positive for pathogenic Leptospira spp. The species detected were L. interrogans, L. borgpetersenii, L. kirschneri, and L. kmetyi by partial 16S rRNA sequencing. We further identified and characterized 11 Leptospira spp. isolates from 8 dogs as serovars Bataviae, Javanica, and Australis. The mortality rate of the Leptospira-infected dogs was high (18 of 53; 34%).

scholarly journals Characterization of a Natural, Stable, Reversible and Colourful Anthocyanidin Network from Sphagnum Moss Based Mainly on the Yellow Trans-Chalcone and Red Flavylium Cation Forms

Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 709
Author(s):  
Helge Berland ◽  
Øyvind M. Andersen
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Cell Wall ◽  
Peat Moss ◽  
Sphagnum Moss ◽  
Naturally Occurring ◽  
Two Component ◽  
Colour System ◽  
The Common ◽  
Cis And Trans

Anthocyanins with various functions in nature are one of the most important sources of colours in plants. They are based on anthocyanidins or 3-deoxyanthocyanidins having in common a C15-skeleton and are unique in terms of how each anthocyanidin is involved in a network of equilibria between different forms exhibiting their own properties including colour. Sphagnorubin C (1) isolated from the cell wall of peat moss (Sphagnum sp.) was in fairly acidic and neutral dimethyl sulfoxide characterized by nuclear magnetic resonance (NMR) and ultraviolet–visible (UV–vis) absorption techniques. At equilibrium, the network of 1 behaved as a two–component colour system involving the reddish flavylium cationic and the yellow trans–chalcone forms. The additional D- and E-rings connected to the common C15-skeleton extend the π-conjugation within the molecule and provide both bathochromic shifts in the absorption spectra of the various forms as well as a low isomerization barrier between the cis- and trans-chalcone forms. The hemiketal and cis-chalcone forms were thus not observed experimentally by NMR due to their short lives. The stable, reversible network of 1 with good colour contrast between its two components has previously not been reported for other natural anthocyanins and might thus have potential in future photochromic systems. This is the first full structural characterization of any naturally occurring anthocyanin chalcone form.

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