Benzoate dioxygenase fromRalstonia eutrophaB9 – unusual regiochemistry of dihydroxylation permits rapid access to novel chirons

Julia A. Griffen; Sarah J. Kenwright; Sarah Abou-Shehada; Scott Wharry; Thomas S. Moody; Simon E. Lewis

doi:10.1039/c3qo00057e

Benzoate dioxygenase fromRalstonia eutrophaB9 – unusual regiochemistry of dihydroxylation permits rapid access to novel chirons

Organic Chemistry Frontiers ◽

10.1039/c3qo00057e ◽

2014 ◽

Vol 1 (1) ◽

pp. 79-90 ◽

Cited By ~ 16

Author(s):

Julia A. Griffen ◽

Sarah J. Kenwright ◽

Sarah Abou-Shehada ◽

Scott Wharry ◽

Thomas S. Moody ◽

...

Keyword(s):

Benzoic Acid ◽

Rapid Access ◽

Benzoate Dioxygenase

Oxidation of benzoic acid by a microorganism expressing benzoate dioxygenase leads to the formation of an unusualipso,orthoarenecis-diol in sufficient quantities to be useful for synthesis.

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A Chemoenzymatic Formal Synthesis of Epoxyquinols A and B

Synlett ◽

10.1055/s-0039-1690216 ◽

2019 ◽

Vol 30 (19) ◽

pp. 2193-2197

Author(s):

Jonathan A. Collins ◽

Christopher J. Gerry ◽

Madeleine M. Duncan

Keyword(s):

Benzoic Acid ◽

Ralstonia Eutropha ◽

Tertiary Alcohol ◽

Subsequent Formation ◽

Formal Synthesis ◽

Whole Cells ◽

Benzoate Dioxygenase

A formal synthesis of epoxyquinols A and B was completed in nine steps starting from benzoic acid. Enantioselectivity was established through an enzymatic arene dihydroxylation reaction performed by whole cells of Ralstonia eutropha B9 expressing benzoate dioxygenase. Subsequent formation of the enone core was facilitated by a Dauben–Michno-type oxidative transposition of an allylic tertiary alcohol.

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Diversity of the gene of benzoate dioxygenase in bacterial associations isolated from long term organochlorine-contaminated soils

Ecological genetics ◽

10.17816/ecogen17313-22 ◽

2019 ◽

Vol 17 (3) ◽

pp. 13-22

Author(s):

Elmira A. Nazarova ◽

Tatyana D. Kiryanova ◽

Daria O. Egorova

Keyword(s):

Benzoic Acid ◽

Contaminated Soils ◽

Bacterial Strains ◽

Chlorobenzoic Acid ◽

Phylogenetic Cluster ◽

Pure Cultures ◽

Total Dna ◽

Bacterial Associations ◽

Benzoate Dioxygenase

Background. Communities of bacteria with specific enzymes are formed in the soil with long-term organochlorine contamination. The aim of this study was to analyze the diversity of the benA gene encoding the -subunit of the benzoate 1,2-dioxygenase in aerobic bacterial associations isolated from the soils of the Chapayevsk-city (Samara region, Russia). Materials and methods. The soil samples were taken on the territory, contaminated with organochlorine compounds for a long time. As a selection factor in the enrichment cultures were used 4-chlorobenzoic acid and chlorobenzene, in the pure cultures benzoic acid. The isolation of total DNA from bacterial associations was performed using a commercial FastDNA Spin Kit for Soil kit (USA). Amplification was performed on a MyCycler instrument (USA). Determination of the nucleotide sequence was performed on an automatic sequencer Genetic Analyzer 3500XL (USA). The search and analysis for benA gene homologs was carried out using international GenBank databases and BLAST system (http://www.ncbi.nlm.nih.gov). Results. As a result of selection, 12 associations of aerobic bacteria were obtained. Fragments of the benA gene (-subunit of benzoate dioxygenase) were obtained with the total DNA of six bacterial associations selected on chlorobenzene and with the total DNA of three bacterial associations selected on 4-chlorobenzoate. Pure cultures of aerobic bacterial strains using benzoic acid as a carbon source were isolated from benA-positive associations. It was established that the amplified fragments with the DNA of the A1, A4, A5, B1, B2, B3, B4 and B6 association strains form a single phylogenetic cluster with the -subunit gene of the benzoate dioxygenase of the Pseudomonas putida strain KT2440 (level of similarity is 9698%). The amplified fragment with the DNA of strain B5-170 (association B5) forms a cluster with the gene of the -subunit of the benzoate dioxygenase of the strain Pseudomonas sp. VLB120 (93% similarity).

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TEM characterization of proton-exchanged LiNbO3 optical waveguides

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010014395x ◽

1986 ◽

Vol 44 ◽

pp. 480-481

Author(s):

W. E. Lee

Keyword(s):

Refractive Index ◽

Benzoic Acid ◽

Optical Waveguides ◽

Total Internal Reflection ◽

Index Of Refraction ◽

Optical Measurements ◽

Lithium Ions ◽

Wide Channel ◽

Tem Characterization

An optical waveguide consists of a several-micron wide channel with a slightly different index of refraction than the host substrate; light can be trapped in the channel by total internal reflection.Optical waveguides can be formed from single-crystal LiNbO3 using the proton exhange technique. In this technique, polished specimens are masked with polycrystal1ine chromium in such a way as to leave 3-13 μm wide channels. These are held in benzoic acid at 249°C for 5 minutes allowing protons to exchange for lithium ions within the channels causing an increase in the refractive index of the channel and creating the waveguide. Unfortunately, optical measurements often reveal a loss in waveguiding ability up to several weeks after exchange.

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