Listeria monocytogenes in Medical Research

Bacteria are known to produce compounds of high value such as secondary metabolites used in biotechnological applications. It is therefore worthwhile to think how to exploit a pathogenic bacterium, e.g., Listeria monocytogenes, to be an effective source of bioactive compound used in particular in medicinal purposes. Listeria monocytogenes is considered as an acute contaminated bacterium in foods and could be a causal agent of food-borne diseases. This bacterium is the causal agent of listeriosis, a grave disease, caused by eating contaminated food. Although, L. monocytogenes is a pathogenic microorganism that threatens the progress of food industry, it would be also a reservoir of secondary metabolites such as antibiotics and other metabolites of economic importance when appropriate strain improvement will be addressed. This section would discuss in brief the negative and positive features of L. monocytogenes as either a pathogenic bacterium or an important microorganism in medical research

Recent Developments in Plant Biotechnology

В этом томе рассматриваются достижения в области биотехнологии растений и основное внимание уделяется использованию липидов и белков, экстрагированных из различных видов тканей растений, в потенциальных промышленных целях. Фактически, липидомика и протеомика относятся к развитию технологий, таких как хроматография и масс-спектрометрия, для изучения липидов и белков. Таким образом, в книге обсуждается важная развивающаяся область исследований, касающаяся использования различных растений для получения соединений с высокой ценностью. Как таковая она понравится читателям, интересующимся медицинскими, биохимическими и биотехнологическими дисциплинами.This volume explores advances in plant biotechnology, and focuses on the use of lipids and proteins extracted from different kinds of plants tissues in potential industrial applications. In fact, lipidomics and proteomics refer to the advancement of technologies, such as chromatography and mass spectrometry, to study lipids and proteins. As such, the book discusses an important emerging field of research concerning the use of different plants to produce compounds with high value. As such, it will appeal to readers with an interest in medical, biochemical, and biotechnological disciplines.Используемые программы Adobe Acroba

Identification of a new oat β-amylase by functional proteomics

International audienceOat (Avena sativa L.) seed extracts exhibited a high degree of catalytic activity including amylase activities. Proteins in the oat seed extracts were optimized for their amylolytic activities. Oat extract with amylolytic activity was separated by SDS-PAGE and a major protein band with an apparent molecular mass of 53 kDa was subjected to tryptic digestion. The generated amino acid sequences were analyzed by liquid chromatography–tandem mass spectrometry (LC/ESI/MS/MS) and database searches. These sequences were used to identify a partial cDNA from expressed sequence tags (ESTs) of A. sativa L. Based upon EST sequences, a predicted full-length gene was identified, with an open reading frame of 1464 bp encoding a protein of 488 amino acid residues (AsBAMY), with a theoretical molecular mass of 55 kDa identified as a β-amylase belonging to the plant β-amylase family. Primary structure of oat β-amylase (AsBAMY) protein indicated high similarity with other β-amylase from other cereals such as wheat (Triticum aestivum), barley (Hordeum vulgare), and rye (Secale cereale) with two conserved Glu residues (E184 and E378) assigned as the “putative” catalytic residues which would act as an acid and base pair in the catalytic process. In addition, a 3D-model of AsBAMY was built from known X-ray structures and sequence alignments. A similar core (β/α)8-barrel architecture was found in AsBAMY like the other cereal β-amylases with a specific location of the active site in a pocket-like cavity structure made at one end of this core (β/α)8-barrel domain suggesting an accessibility of the non-reducing end of the substrate and thus confirming the results of AsBAMY exo-acting hydrolase

Optimised amylases extraction from oat seeds and its impact on bread properties

International audienceStatistical approaches were employed for the optimisation of the extraction of amylolytic activity from oat (Avena sativa) seeds. The application of the response surface methodology allows us to determine a set of optimal conditions (ratio seed weight/buffer volume 0.1, germination days 10 days, temperature 20 °C and pH 5.6). Experiments carried out under these conditions led to amylase production yield of 91 U/g. Its maximal activity was in the pH 5.6 and at 55 °C. Study of the incorporation of the optimised oat extract into the bread formulation revealed an improvement of the sensory quality and the textural properties of fresh and stored bread. Three-dimensional elaborations of Confocal Laser Scanning Microscopy (CLSM) images were performed on crumb of the different breads to evaluate the influence of amylase activity on microstructure. The result showed improved baking characteristics as well as overall microscopic and macroscopic appearance