Enzymatic degradation of ochratoxin A in the gastrointestinal tract of piglets.

Animal feeds are often contaminated with ochratoxin A (OTA), a potent natural mycotoxin hazardous to animal and human health that accumulates in blood and tissues. To the best of our knowledge, this study is the first to investigate the in vivo application of an enzyme (OTA amidohydrolase; OAH) that degrades OTA into the nontoxic molecules phenylalanine and ochratoxin α (OTα) in the gastrointestinal tract (GIT) of pigs. Piglets were fed six experimental diets over 14 days, varying in OTA contamination level (50 or 500 μg/kg; OTA50 and OTA500) and presence of OAH; a negative control diet (no OTA added) and a diet containing OTα at 318 µg/kg (OTα318).

Ochratoxin A degrading enzymes of Stenotrophomonassp. 043-1a.

Ochratoxin A is a secondary metabolite that acts as a mycotoxin and is produced by Aspergillus, Penicillium, and other fungal species. It is a threat to animal and human health due to nephrotoxic, carcinogenic, and genotoxic properties and its widespread incidence in agricultural products. To reduce this threat, biological remediation processes are of growing interest.

Toolbox for the Extraction and Quantification of Ochratoxin A and Ochratoxin Alpha Applicable for Different Pig and Poultry Matrices.

Ochratoxin A (OTA) is one of the major mycotoxins causing severe effects on the health of humans and animals. Ochratoxin alpha (OTα) is a metabolite of OTA, which is produced through microbial or enzymatic hydrolysis, and one of the preferred routes of OTA detoxification. The methods described here are applicable for the extraction and quantification of OTA and OTα in several pig and poultry matrices such as feed, feces/excreta, urine, plasma, dried blood spots, and tissue samples such as liver, kidney, muscle, skin, and fat.

An In Silico Target Fishing Approach to Identify Novel Ochratoxin A Hydrolyzing Enzyme.

Ochratoxin A (OTA), a mycotoxin that is of utmost concern in food and feed safety, is produced by fungal species that mainly belong to the and genera. The development of mitigation strategies to reduce OTA content along the supply chains is key to ensuring safer production of food and feed. Enzyme-based strategies are among the most promising methods due to their specificity, efficacy, and multi-situ applicability.

Structure and mechanism of benzaldehyde dehydrogenase from Pseudomonas putida ATCC 12633, a member of the Class 3 aldehyde dehydrogenase superfamily.

Benzaldehyde dehydrogenase from Pseudomonas putida (PpBADH) belongs to the Class 3 aldehyde dehydrogenase (ALDH) family. The Class 3 ALDHs are unusual in that they are generally dimeric (rather than tetrameric), relatively non-specific and utilize both NAD+ and NADP+. To date, X-ray structures of three Class 3 ALDHs have been determined, of which only two have cofactor bound, both in the NAD+ form.

Revisiting the lipase from Pseudomonas aeruginosa: directed evolution of substrate acceptance and enantioselectivity using iterative saturation mutagenesis.

The most thoroughly studied enzyme in directed evolution is the lipase from Pseudomonas aeruginosa (PAL) as a catalyst in the hydrolytic kinetic resolution of 2-methyldecanoic acid p-nitrophenyl ester. Seminal studies utilized epPCR, saturation mutagenesis and DNA shuffling or combinations thereof. With current emphasis on efficacy in laboratory evolution, however, we recently applied our previously developed method, iterative saturation mutagenesis (ISM), to the same catalytic system, discovering that this approach is much more efficient than the original strategies.

Nitrile hydratases (NHases): at the interface of academia and industry.

Nitrile hydratase (NHase, EC 4.2.1.

Iterative saturation mutagenesis accelerates laboratory evolution of enzyme stereoselectivity: rigorous comparison with traditional methods.

Efficacy in laboratory evolution of enzymes is currently a pressing issue, making comparative studies of different methods and strategies mandatory. Recent reports indicate that iterative saturation mutagenesis (ISM) provides a means to accelerate directed evolution of stereoselectivity and thermostability, but statistically meaningful comparisons with other methods have not been documented to date. In the present study, the efficacy of ISM has been rigorously tested by applying it to the previously most systematically studied enzyme in directed evolution, the lipase from Pseudomonas aeruginosa as a catalyst in the stereoselective hydrolytic kinetic resolution of a chiral ester.

Improved PCR method for the creation of saturation mutagenesis libraries in directed evolution: application to difficult-to-amplify templates.

Saturation mutagenesis constitutes a powerful method in the directed evolution of enzymes. Traditional protocols of whole plasmid amplification such as Stratagene's QuikChange sometimes fail when the templates are difficult to amplify. In order to overcome such restrictions, we have devised a simple two-primer, two-stage polymerase chain reaction (PCR) method which constitutes an improvement over existing protocols.

Acrylamide synthesis using agar entrapped cells of Rhodococcus rhodochrous PA-34 in a partitioned fed batch reactor.

The nitrile hydratase (Nhase) induced cells of Rhodococcus rhodochrous PA-34 catalyzed the conversion of acrylonitrile to acrylamide. The cells of R. rhodochrous PA-34 immobilized in 2% (w/v) agar (1.