Degradation of (+/-)-synephrine by Arthrobacter synephrinum. Oxidation of 3,4-dihydroxyphenylacetate to 2-hydroxy-5-carboxymethyl-muconate semialdehyde.

1. Cell-free extracts of Arthrobacter synephrinum catalyse the oxidation of 3,4-dihydroxy-phenylacetate. 2. The product of oxidation was characterized as 2-hydroxy-5-carboxymethylmuconate semialdehyde from its chemical behaviour as well as from nuclear-magnetic-resonance spectra. 3. A 3,4-dihydroxyphenylacetate 2,3-dioxygenase (EC 1.13.11.15) was partially purified from A. synephrinum. 4. The enzyme had a Km of 25 micrometer towards its substrate and exhibited typical Michaelis-Menten kinetics. 5. The enzyme also catalysed the oxidation of 3,4-dihydroxymandelate and 3,4-dihydroxyphenylpropionate, at reaction rates of 0.5 and 0.04 respectively of that for 3,4-dihydroxyphenylacetate. 6. The enzyme was sensitive to treatment with thiol-specific reagents. 7. The molecular weight of the enzyme as determined by Sephadex G-200 chromatography was approx. 282000.     

Chiral Imidazolidin-4-one with catalytic amount of Dicationic ionic liquid act as a recoverable and reusable Organocatalyst for asymmetric Diels-Alder reaction

Imidazolidin-4-one is used as a recoverable organocatalyst for the asymmetric Diels-Alder reaction in the presence of catalytic amount of dicationic ionic liquid and trifluoroacetic acid as a co-catalyst. The Diels-Alder reaction between model substrate cyclopentadiene and crotonaldehyde gave the product in 95% conversion and 87% ee of the endo-product. The catalyst was shown better reusability when the 20 mol% of dicationic ionic liquid was used and catalyst was reused upto 5 cycles, conversion remains upto 3 recycles but ee of endo- 9 was slightly droped.     

A single-nucleotide polymorphism in tumor necrosis factor-α (− 308 G/A) as a biomarker in chronic pancreatitis

Objective

Chronic pancreatitis is a gradual, long-term inflammation of the pancreas that results in alteration of its normal structure and function. The study aims to investigate the role of − 308 (G/A) polymorphism of TNF-α gene in chronic pancreatitis.

Material and methods

A total of 200 subjects were included in this case–control study. A total of 100 in patients admitted in the Gastroenterology Unit of Gandhi Hospital and Osmania General Hospital, Hyderabad were included in the present study. An equal number of healthy control subjects were randomly selected for the study. The genotyping of TNF-α gene was carried out by tetra-primer ARMS PCR followed by gel electrophoresis. The TNF-α levels were assayed by enzyme-linked immunosorbent assay.

Results

A significant variation with respect to the genotypic and allelic distribution in the disease group when compared to control subjects [OR = 2.001 (1.33–3.005), p < 0.0001**] was observed. Subjects homozygous for the A allele had higher TNF-α levels compared to G allele.

Conclusion

The present study revealed a significant association of the TNF-α gene promoter polymorphism with chronic pancreatitis. Thus, TNF-α genotype can be considered as one of the biological markers in the etiology of chronic pancreatitis.     

Influence of trace elements on biogas production from mango processing waste in 1.5 m3 KVIC digesters

Summary The influence of trace elements (Co²⁺, Ni²⁺ and Fe³⁺) in varying concentrations and combination, was studied in 1.5 m³ Khadi & Village Industries Commission (KVIC) digesters for biogas generation from mangopeel. Addition of these trace metals enhanced the biogas yield and methane content moderately, the maximum being with the iron fed digester. The digesters were always found to be stable without much variation in total volatile fatty acids (VFA), pH, total alkalinity and other parameters. A methane content of 62% and biogas yield of 0.49 m³/kg VS added was obtained with 4000 mg/L FeCl₃ supplemented mangopeel fed digester as compared to control having biogas yield of 0.22 m³/kg VS added with a methane content of about 48–50%.     

Dynamic changes to the endocannabinoid system in models of chronic pain

The analgesic effects of cannabinoid ligands, mediated by CB1 receptors are well established. However, the side-effect profile of CB1 receptor ligands has necessitated the search for alternative cannabinoid-based approaches to analgesia. Herein, we review the current literature describing the impact of chronic pain states on the key components of the endocannabinoid receptor system, in terms of regionally restricted changes in receptor expression and levels of key metabolic enzymes that influence the local levels of the endocannabinoids. The evidence that spinal CB2 receptors have a novel role in the modulation of nociceptive processing in models of neuropathic pain, as well as in models of cancer pain and arthritis is discussed. Recent advances in our understanding of the spinal location of the key enzymes that regulate the levels of the endocannabinoid 2-AG are discussed alongside the outcomes of recent studies of the effects of inhibiting the catabolism of 2-AG in models of pain. The complexities of the enzymes capable of metabolizing both anandamide (AEA) and 2-AG have become increasingly apparent. More recently, it has come to light that some of the metabolites of AEA and 2-AG generated by cyclooxygenase-2, lipoxygenases and cytochrome P450 are biologically active and can either exacerbate or inhibit nociceptive signalling.     

Favored and less favored codon–anticodon duplexes arising from the GC codon family box encoding for alanine: some computational perspectives

Alanine is encoded by the four codons of the GC box (GCA, GCG, GCU, and GCC). Known alanine anticodons include the UGC, IGC, and VGC triplets (I = inosine; V = uridine-5-oxyacetic acid). The energy-minimized structures of all possible codon–anticodon combinations involving all the alanine codons GCA, GCG, GCU, and GCC with the alanine anticodons UGC, IGC, and VGC are studied using the AMBER software. Fifteen H-bonded duplex structures arising out of these combinations are studied here, all having Watson–Crick-type base pairs at the first and second codon positions, and a variety of base pairing possibilities at the third (or wobble) position. Structural and stability considerations suggest that some codon–anticodon duplexes would be more favored than others for accommodation during the translation process. The UGC anticodon is predicted to favor the GCA codon for reading, while the GCC codon is least favored. The IGC anticodon would prefer to read the GCC codon, the GCG codon being least favored, while a syn conformer for A in the GCA codon could allow for it to be read. For the VGC anticodon, the GCA codon is predicted to be read most favorably, and the GCC codon least favorably, while a syn conformer for V in the anticodon would allow for the codon GCU to be read through a wobble pair which involves the exocyclic 5-oxyacetate group of V in H-bonding.