Bacterial laccases: some recent advances and applications

Laccases belong to the large family of multi-copper oxidases (MCOs) that couple the one-electron oxidation of substrates with the four-electron reduction of molecular oxygen to water. Because of their high relative non-specific oxidation capacity particularly on phenols and aromatic amines as well as the lack of requirement for expensive organic cofactors, they have found application in a large number of biotechnological fields. The vast majority of studies and applications were performed using fungal laccases, but bacterial laccases show interesting properties such as optimal temperature above 50 °C, optimal pH at the neutral to alkaline range, thermal and chemical stability and increased salt tolerance. Additionally, bacterial systems benefit from a wide range of molecular biology tools that facilitates their engineering and achievement of high yields of protein production and set-up of cost-effective bioprocesses. In this review we will provide up-to-date information on the distribution and putative physiological role of bacterial laccases and highlight their distinctive structural and biochemical properties, discuss the key role of copper in the biochemical properties, discuss thermostability determinants and, finally, review biotechnological applications with a focus on catalytic mechanisms on phenolics and aromatic amines.info:eu-repo/semantics/publishedVersio

Crop Production, Gender Roles and the Use of Mobile Phones and Radios for Agricultural Information by Farmers in Apac District, Northern Uganda

The introduction of information communication technologies like mobile phones and radios as a form of agricultural extension has the capacity to alter household gender roles. The information access that was previously more available to men than women, has the capacity to empower farmers by improving their ability to turn food crops into market oriented crops. This implies that food crops, previously seen as women’s crops, also become cash crops, which were thought to be men’s crops. This change also leads to changes in agricultural gender roles. The anticipated increase in agricultural productivity also leads to men or hired labour participating in agricultural roles that were previously thought to be women’s roles, so as to meet the market demands in a timely manner. The dual purpose of the crops leads to more joint labour provision along the agricultural production process and blurs the gender divide. The study used a sequentially mixed methods’ approach among farmers belonging to five farmer groups in Apac district in Northern Uganda. The study indicated that the use of mobile phones in agricultural production altered agricultural gender roles, as well as the participation of women and men in the production of food crops and cash crops. The changes greatly benefited women farmers as they moved into commercial production alongside their husbands, which changed their socio-economic status. The use of mobile phones and radios is important in fostering the participation of both men and women in agricultural roles that they previously did not engage in, since there is limited monopoly of information once a couple navigates issues of power relations surrounding the access to and use of the technologies

Depletion of Normal and Malignant B cells with a CD37-specific SMIP molecule

3063 Background: CD37 is a member of the tetraspanin family expressed at high levels by normal mature B cells and by most B cell malignancies. Previously, an antibody to CD37 has been labeled with 131I and tested in clinical trials for therapy of NHL. Treatment with 131I-MB-1, resulted in durable tumor remissions in patients lasting from 4 to 11 months (Press OW, Eary JF, Badger CC, et al. Treatment of refractory non-Hodgkin’s lymphoma with radiolabeled MB-1 (anti-CD37) antibody. J Clin Oncol. 1989;7:1027–1038). Here we assess the functional properties and therapeutic potential of a small modular immunopharmaceutical (SMIP) targeting CD37. Methods: Growth arrest and apoptosis of B lymphoma cell lines was assessed. ADCC activity was evaluated using BJAB targets and human peripheral blood mononuclear cells (PBMC) effectors. Drug-drug interactions were assessed by the Combination Index method. In vivo studies were performed utilizing established human B cell tumor xenografts in nude mice. Results: A CD37-directed SMIP drug candidate mediated growth arrest, apoptosis and ADCC, but not CDC, towards B lymphoma cell lines. The protein showed significant anti-tumor activity in a mouse xenograft model, and selectively depleted normal human B cells in short term cultures of PBMC. When combined with rituximab, the molecule increased apoptosis, C1q binding, and C’ dependent target cell death in vitro, and increased anti-tumor activity in vivo in a xenograft model. Conclusions: In vitro and in vivo characterization of the CD37-targeted SMIP drug suggest a potent capacity to eliminate target cells through combined effects of direct target cell signaling and effector cell recruitment. CD37-mediated growth was synergistic with standard chemotherapies in vitro and showed additive in vivo activity with CD20-targeted therapy. On the basis of these data CD37-directed SMIP therapy is being developed for clinical evaluation against B cell malignancies. No significant financial relationships to disclose. </jats:p

Posttranslational mutagenesis: A chemical strategy for exploring protein side-chain diversity

Post-translational modification of proteins expands their structural and functional capabilities beyond those directly specified by the genetic code. However, the vast diversity of chemically-plausible (including unnatural but functionally relevant) side-chains is not readily accessible. We describe C(sp3)–C(sp3) bond-forming reactions on proteins under biocompatible conditions, which exploit unusual carbon free radical chemistry, and use them to form C–C bonds with altered side chains. We demonstrate how these transformations enable a wide-diversity of natural, unnatural, post-translationally-modified (methylated, glycosylated, phosphorylated, hydroxylated) and labeled (fluorinated, isotopically-labeled) side-chains to be added to a common, readily-accessible dehydroalanine precursor in a range of representative protein types and scaffolds. This approach, outside of the rigid constraints of the ribosome and enzymatic processing, may be modified more generally for accessing diverse proteins

Posttranslational mutagenesis: A chemical strategy for exploring protein side-chain diversity

Posttranslational modification of proteins expands their structural and functional capabilities beyond those directly specified by the genetic code. However, the vast diversity of chemically-plausible (including unnatural but functionally relevant) side-chains is not readily accessible. We describe C (sp3)–C (sp3) bond-forming reactions on proteins under biocompatible conditions, which exploit unusual carbon free radical chemistry, and use them to form Cβ–Cγ bonds with altered side chains. We demonstrate how these transformations enable a wide-diversity of natural, unnatural, posttranslationally-modified (methylated, glycosylated, phosphorylated, hydroxylated) and labeled (fluorinated, isotopically-labeled) side-chains to be added to a common, readily-accessible dehydroalanine precursor in a range of representative protein types and scaffolds. This approach, outside of the rigid constraints of the ribosome and enzymatic processing, may be modified more generally for accessing diverse proteins

Posttranslational mutagenesis: A chemical strategy for exploring protein side-chain diversity

Copyright © 2016, American Association for the Advancement of Science. Posttranslational modification of proteins expands their structural and functional capabilities beyond those directly specified by the genetic code. However, the vast diversity of chemically plausible (including unnatural but functionally relevant) side chains is not readily accessible. We describe C (sp3)-C (sp3) bond-forming reactions on proteins under biocompatible conditions, which exploit unusual carbon free-radical chemistry, and use them to form Cβ-Cγ bonds with altered side chains. We demonstrate how these transformations enable a wide diversity of natural, unnatural, posttranslationally modified (methylated, glycosylated, phosphorylated, hydroxylated), and labeled (fluorinated, isotopically labeled) side chains to be added to a common, readily accessible dehydroalanine precursor in a range of representative protein types and scaffolds. This approach, outside of the rigid constraints of the ribosome and enzymatic processing, may be modified more generally for access to diverse proteins