Search

Thiamine diphosphate (ThDP) dependent carboligases catalyze the formation of carbon‐carbon bonds. These enzymes are prominent biocatalysts for the production of valuable α‐hydroxy carbonyl compounds, which serve as key building blocks in the synthesis of various pharmaceuticals and fine chemicals. Carboligases act in selective manner to afford regio‐ and stereochemically defined products from simple starting materials. This review explores the catalytic prowess of carboligases for synthetic purposes and is aimed at providing a selection tool of enzymes for particular sets of substrates or desired products. The comprehensive overview encompasses structural insights, relationships of the currently known sequence space and practical applications with a focus on recent literature, showcasing carboligases as potent tools for sustainable and efficient synthesis. [ABSTRACT FROM AUTHOR]

This is a collective interpretive record of a graduate course in Social Work on participatory action research (PAR) offered during the winter of 2007. It is written by 14 individuals including the instructor. It was inspired by the image of a chickadee bird borrowed from Jonathan Lear's (2006) book "Radical Hope." The chickadee is a powerful metaphor for aboriginal peoples of Western Canada as she thrives in the bitter winters despite her tiny frame. She does so because she is gifted with deep listening in her environment wherein lies all she needs to know. The class of 14 met in a circle, read articles, kept learning journals, argued, ate together, practised popular education techniques and presented our emerging knowledge in multi-media forms. We related our experience to recent articles in EAR and to other PAR literature. The chickadee facilitated our deep listening to writings and to our own stories. Collective power emerged from our relationships and our diversity.

Within human biology, combinations of regioisomeric motifs of α2,6- or α2,3-sialic acids linked to galactose are frequently observed attached to glycoconjugates. These include glycoproteins and glycolipids, with each linkage carrying distinct biological information and function. Microbial linkage-specific sialidases have become important tools for studying the role of these sialosides in complex biological settings, as well as being used as biocatalysts for glycoengineering. However, currently, there is no α2,6-specific sialidase available. This gap has been addressed herein by exploiting the ability of a Photobacterium sp. α2,6-sialyltransferase to catalyze trans-sialidation reversibly and in a highly linkage-specific manner, acting as a pseudosialidase in the presence of cytidine monophosphate. Selective, near quantitative removal of α2,6-linked sialic acids was achieved from a wide range of sialosides including small molecules conjugates, simple glycan, glycopeptide and finally complex glycoprotein including both linkages. [ABSTRACT FROM AUTHOR]

β(1,4)-Galactosyltransferase (β4Gal-T1) and T. cruzi trans-sialidase (TcTS) have been used in a ‘one-pot’ cascade to provide vesicles (liposomes) with a trisaccharide coating. These soluble enzymes catalysed the transfer of galactose then sialic acid onto a synthetic N-acetylglucolipid embedded in the bilayers. Clustering of this substrate into microdomains increased the rate of sialylated lipid production, showing that an increase in β4Gal-T1 activity is carried through the enzymatic cascade. These coatings modulated cell recognition. Hepatocellular carcinoma cells took up vesicles modified by β4Gal-T1 alone more extensively than sialylated vesicles produced by ‘one-pot’ sequential enzymatic modification. [ABSTRACT FROM AUTHOR]

This review comprehensively covers the most recent achievements (from 2013) in the successful integration of nanomaterials in the field of glycomics. The first part of the paper addresses the beneficial properties of nanomaterials for the construction of biosensors, bioanalytical devices, and protocols for the detection of various analytes, including viruses and whole cells, together with their key characteristics. The second part of the review focuses on the application of nanomaterials integrated with glycans for various biomedical applications, that is, vaccines against viral and bacterial infections and cancer cells, as therapeutic agents, for in vivo imaging and nuclear magnetic resonance imaging, and for selective drug delivery. The final part of the review describes various ways in which glycan enrichment can be effectively done using nanomaterials, molecularly imprinted polymers with polymer thickness controlled at the nanoscale, with a subsequent analysis of glycans by mass spectrometry. A short section describing an active glycoprofiling by microengines (microrockets) is covered as well. [ABSTRACT FROM AUTHOR]

Enantiomerenreine, chirale Amine sind unentbehrliche Bausteine in bioaktiven Pharmazeutika, und ihre Synthese aus einfachen Startmaterialien ist daher von großem Interesse. Eine der vielversprechendsten Strategien ist die chemisch anspruchsvolle, stereoselektive Synthese chiraler Amine durch eine C‐H‐Aminierung. Hier berichten wir über den Einsatz einer Multienzym‐Kaskade, generiert in einer einzelnen bakteriellen Ganzzelle, die es möglich macht, stereoselektive Aminierungen in Benzylposition mit ee‐Werten von 97.5 % zu katalysieren. Die Kaskade nutzt dabei vier heterolog exprimierte, rekombinante Enzyme, wobei die nötigen Kofaktoren von der Wirtzelle bereitgestellt werden und Isopropylamin als Aminodonor extern zugegeben wird. Diese Kaskade repräsentiert damit das erste Beispiel eines erfolgreichen De‐novo‐Designs eines einzelnen Ganzzellen‐Biokatalysators für die formale stereoselektive C‐H‐Aminierung. Enantiomerenreine, chirale Amine sind unentbehrliche Bausteine in bioaktiven Pharmazeutika, und ihre Synthese aus einfachen Startmaterialien ist daher von großem Interesse. Eine Strategie ist die stereoselektive Synthese chiraler Amine durch C‐H‐Aminierung. Eine Multienzym‐Kaskade, generiert in einer einzelnen bakteriellen Ganzzelle, ermöglicht es, stereoselektive Aminierungen in Benzylposition mit 97.5 % ee zu katalysieren. [ABSTRACT FROM AUTHOR]

Enantiomerically pure chiral amines are ubiquitous chemical building blocks in bioactive pharmaceutical products and their synthesis from simple starting materials is of great interest. One of the most attractive strategies is the stereoselective installation of a chiral amine through C−H amination, which is a challenging chemical transformation. Herein we report the application of a multienzyme cascade, generated in a single bacterial whole-cell system, which is able to catalyze stereoselective benzylic aminations with ee values of 97.5 %. The cascade uses four heterologously expressed recombinant enzymes with cofactors provided by the host cell and isopropyl amine added as the amine donor. The cascade presents the first example of the successful de novo design of a single whole-cell biocatalyst for formal stereoselective C−H amination. [ABSTRACT FROM AUTHOR]

This article draws on the findings of diversity audit study done at the East Area Office of the City of Calgary, in Canada. It identifies existing strengths and gaps in addressing diversity and social inclusion within the office staff and in the program planning, design and delivery to the diverse communities in the east of Calgary. • Findings: Although staff of the area office feel a strong sense of belong in the workplace and work collaboratively with each other in different streams, it was identified that more collaboration needs to be established between the community social workers and community recreation coordinators. It was also found that almost all staff in the area office have no knowledge for procedures to report discrimination in the work place. On the other hand, the community consultations have identified that East Area Office needs to develop close relationship with gay, lesbian, bisexual and transgendered communities, which at the time of the study were not specifically targeted with programs by the office. • Application: Building from the disconnect between program planning, design and delivery on the one hand, and the inclusion of all the diverse communities on the other hand, the authors present opportunities for dialogue and partnership development to enhance collaborative work between the communities and the East Area Office. Through this collaboration, programs will be planned, designed and delivered with appropriate cultural sensitivity. As well, the authors emphasize the need to strengthen collaborative work between the community social workers (CSWs) and the community recreation coordinators (CRCs), which are the two staff streams working in East Area Office so that their efforts can complement each other. [ABSTRACT FROM AUTHOR]

The article looks into the structure and biosynthesis of an unusual S-linked glycan linkage in the antibacterial glycopeptide sublancin. It discusses the function of the protein glycosylation in higher organisms with the majority belongings to N-glycans, O-glycans and GPI anchors. Furthermore, the study notes the role of the S-glycosides on the hydrolytically stable biosimilars to their equivalent-glycosides.

Enantiomerenreine chirale Amine sind allgegenwärtige chemische Bausteine in bioaktiven Pharmazeutika. Eine der interessantesten Strategien für ihre Synthese ist der stereoselektive Aufbau eines chiralen Amins durch formale C‐H‐Aminierung. S. Flitsch et al. berichten in der Zuschrift auf S. 1533 ff. über die Entwicklung und Anwendung einer Multienzym‐Kaskade, die stereoselektive Aminierungen in Benzylposition katalysieren kann, in einer einzelnen bakteriellen Ganzzelle. [ABSTRACT FROM AUTHOR]

The cover page of the article "Whole-Cell Biocatalysts for Stereoselective C-H Amination Reactions," is presented.

Sialic acids are sugars present in many animal glycoproteins and are of particular interest in biopharmaceuticals, where a lack of sialylation can reduce bioactivity. Here, we describe how α-2,6-sialyltransferase from Photobacterium damselae can be used to markedly increase the level of sialylation of CHO-produced α-1-antitrypsin. Detailed analysis of the sialylation products showed that in addition to the expected α-2,6-sialylation of galactose, a second disialyl galactose motif Neu5Ac-α2,3(Neu5Ac-α2,6)Gal was produced, which, to our knowledge, had never been detected on a mammalian glycoprotein. We exploited this disialyl galactose activity of the P. damselae in a multienzyme reaction to produce a highly sialylated α-1-antitrypsin. The influence of this unique disialylation on the in vitro activity of α-1-antitrypsin was studied, and a toolkit of mass spectrometry methods for identifying this new disialyl galactose motif in complex mixtures was developed.