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A novel heterogeneous enzyme-palladium (Pd) (0) nanoparticles (PdNPs) bionanohybrid has been synthesized by an efficient, green, and straightforward methodology. A designed Geobacillus thermocatenulatus lipase (GTL) variant genetically and then chemically modified by the introduction of a tailor-made cysteine-containing complementary peptide- was used as the stabilizing and reducing agent for the in situ formation of ultra-small PdNPs nanoparticles embedded on the protein structure. This bionanohybrid was an excellent catalyst in the synthesis of trans-ethyl cinnamate by Heck reaction at 65 ◦C. It showed the best catalytic performance in dimethylformamide (DMF) containing 10–25% of water as a solvent but was also able to catalyze the reaction in pure DMF or with a higher amount of water as co-solvent. The recyclability and stability were excellent, maintaining more than 90% of catalytic activity after five cycles of use. ; This work has been sponsored by the Spanish Government (Project AGL2017-84614-C2-2-R) and CSIC Project CSIC-PIE 201880E011). ; Peer reviewed

This article belongs to the Special Issue Catalysts for a Green Chemistry: A Themed Issue Honoring Professor Roger Sheldon for His Contribution in the Field of the Green Chemistry with the Introduction of the E Factor. ; Different materials containing carboxylic groups have been functionalized with geranyl-amine molecules by using an EDC/NHS strategy. Chemical modification of the support was confirmed by XRD, UV-spectrophotometer, and FT-IR. This geranyl-functionalized material was successfully applied for four different strategies of site-selective immobilization of proteins at room temperature and aqueous media. A reversible hydrophobic immobilization of proteins (lipases, phosphoglucosidases, or tyrosinase) was performed in neutral pH in yields from 40 to >99%. An increase of the activity in the case of lipases was observed from a range of 2 to 4 times with respect to the initial activity in solution. When chemically or genetically functionalized cysteine enzymes were used, the covalent immobilization, via a selective thiol-alkene reaction, was observed in the presence of geranyl support at pH 8 in lipases in the presence of detergent (to avoid the previous hydrophobic interactions). Covalent attachment was confirmed with no release of protein after immobilization by incubation with hydrophobic molecules. In the case of a selenium-containing enzyme produced by the selenomethionine pathway, the selective immobilization was successfully yielded at acidic pH (pH 5) (89%) much better than at pH 8. In addition, when an azido-enzyme was produced by the azide–homoalanine pathway, the selective immobilization was successful at pH 6 and in the presence of CuI for the click chemistry reaction. ; This work was sponsored by the Spanish Government (Project No. AGL2017-84614-C2-2-R, AEI/FEDER) and CSIC Project No. CSIC-PIE 201880E011. ; Peer reviewed

The ability to degrade ochratoxin A was studied in different bacteria with a well-known capacity to transform aromatic compounds. Strains belonging to Rhodococcus, Pseudomonas, and Brevibacterium genera were grown in liquid synthetic culture medium containing ochratoxin A. Brevibacterium spp. strains showed 100% degradation of ochratoxin A.Ochratoxin ¿ was detected and identified by high-performance liquid chromatographymass spectrometry (HPLC-MS) as a degradation product in the cellfree supernatants. The degradation of ochratoxin A is of public concern for food and environmental safety, because it could contribute to the development of new biological ochratoxin A detoxification systems in foodstuffs. In this study, the degradation of ochratoxin A by bacteria belonging to the food chain was demonstrated for the first time. ; This work was supported by the "ASER" grant (D.M 16101/7301/08) from the Italian Ministero delle Politiche Agricole Alimentari e Forestali and by grants RM2008-00002 (Instituto Nacional de Investigación Agraria y Alimentaria), AGL2008-01052, Consolider INGENIO 2010 CSD2007-00063 FUN-C-FOOD (Comisión Interministerial de Ciencia y Tecnología), and S2009/AGR-1469 (ALIBIRD) (Comunidad de Madrid). ; Peer Reviewed

In situ extractive fermentation was used to produce 4-vinyl derivatives from hydroxycinnamic acids extracted from corn cobs by recombinant Escherichia coli cells expressing Lactobacillus plantarum phenolic acid descarboxylase (PAD) gene. This microorganism mainly produced 4-vinylphenol (4VP) from p-coumaric acid (p-CA). In a first study, we observed that concentrations of 4VP higher than 1 g/L had a negative impact on descarboxylation of p-CA to 4VP by recombinant E.coli cells. Because of this, and in order to improve the downstream process, a two-phase aqueous-organic solvent system was developed. The results of the extractive fermentation indicated that it was possible to use hydrolyzates as aqueous phase to bioproduce 4VP, and recover simultaneously the product in the organic phase containing hexane. The detoxification of pre-treated corn cob alkaline hydrolyzate improved 4VP production up to 1003.5 mg/L after 24 h fermentation (QP = 41.813 mg/L·h). Additionally, preliminary experiments using cells immobilized in calcium alginate showed to be a good system for the biotransform of p-CA to 4VP in extractive fermentation, although the process hindered partially the recovery of 4VP in the organic phase. ; We are grateful to the Spanish Ministry of Science and Innovation for the financial support of this work (CTQ2011-28967 and AGL2011-22745 projects), which has partial financial support from the FEDER funds of the European Union. J.M.S. is grateful for Postdoctoral fellowship (SFRH / BPD / 84440 / 2012) of Fundacao para a Ciencia e Tecnologia - ...

In situ extractive fermentation was used to produce 4-vinyl derivatives from hydroxycinnamic acids extracted from corn cobs by recombinant Escherichia coli cells expressing Lactobacillus plantarum phenolic acid descarboxylase (PAD) gene. This microorganism mainly produced 4-vinylphenol (4VP) from p-coumaric acid (p-CA). In the first study , we observed that the concentrations of 4VP are higher than 1g/L which had a negative impact on decarboxylation of p-CA to 4VP by recombinant E. coli cells. Because of this, and in order to improve the downstream process, a two-phase aqueous-organic solvent system was developed. The results of the extractive fermentation indicated that it was possible to use hydrolyzates as aqueous phase to bioproduce 4VP, and recover simultaneously the product in the organic phase containing hexane. The detoxification of pre-treated corn cob alkaline hydrolyzate improved 4VP production up to 1003.5mg/L after 24h fermentation (QP=41.813mg/Lh). Additionally, preliminary experiments using cells immobilized in calcium alginate showed to be a good system for the biotransform of p-CA to 4VP in extractive fermentation, although the process hindered partially the recovery of 4VP in the organic phase. © 2014 Elsevier Inc. ; Spanish Ministry of Science and Innovation for the financial support of this work (CTQ2011-28967 and AGL2011-22745 projects), which has partial financial support from the FEDER funds of the European Union. J.M.S. is grateful for Postdoctoral fellowship (SFRH / BPD / 84440 / 2012) of Fundação para a Ciência e Tecnologia – FCT. ; Peer Reviewed

Different Pd-complexes containing orthometallated push–pull oxazolones were inserted by supramolecular Pd-amino acid coordination on two genetically engineered modified variants of the thermoalkalophilic Geobacillus thermocatenolatus lipase (GTL). Pd-lipase conjugation was performed on the solid phase in the previously immobilized form of GTL under mild conditions, and soluble conjugated Pd-GTL complexes were obtained by simply desorbing by washing with an acetonitrile aqueous solution. Three different Pd complexes were incorporated into two different genetically modified enzyme variants, one containing all the natural cysteine residues changed to serine residues, and another variant including an additional Cys mutation directly in the catalytic serine (Ser114Cys). The new Pd–enzyme conjugates were fluorescent even at ppm concentrations, while under the same conditions free Pd complexes did not show fluorescence at all. The Pd conjugation with the enzyme extremely increases the catalytic profile of the corresponding Pd complex from 200 to almost 1000-fold in the hydrogenation of arenes in aqueous media, achieving in the case of GTL conjugated with orthopalladated 4a an outstanding TOF value of 27 428 min−1. Also the applicability of GTL-C114 conjugated with orthopalladated 4b in a site-selective C–H activation reaction under mild conditions has been demonstrated. Therefore, the Pd incorporation into the enzyme produces a highly stable conjugate, and improves remarkably the catalytic activity and selectivity, as well as the fluorescence intensity, of the Pd complexes. ; We thank the Spanish National Research Council (CSIC, Spain), the Aragón Government (Spain, Project LMP144_18: Programa Operativo FEDER Aragón 2014-2020, "Construyendo Europa desde Aragón" and research group Aminoácidos y Péptidos E19_20R) and the Spanish Government (Ministerio de Ciencia e Innovación) (Projects No. AGL2017-84614-C2-2-R and PID2019-106394GB-I00) for funding. Authors thank the European Cooperation in Science and Technology (COST) program under CA15106 grant (CHAOS: CH Activation in Organic Synthesis). A. P. is grateful for the financial support of the Romanian Ministry of Education and Research through the grant PN-III-P1-1.1-MC-2018-2580. ; We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI). ; Peer reviewed

Three novel glycosidases produced from Lactobacillus plantarum, so called Lp_0440, Lp_2777, and Lp_3525, were isolated and overexpressed on Escherichia coli containing a His-tag for specific purification. Their specific activity was evaluated against the hydrolysis of p-nitrophenylglycosides and p-nitrophenyl-6-phosphate glycosides (glucose and galactose) at pH 7. All three were modified with hyaluronic acid (HA) following two strategies: A simple coating by direct incubation at alkaline pH or direct chemical modification at pH 6.8 through preactivation of HA with carbodiimide (EDC) and N-hydroxysuccinimide (NHS) at pH 4.8. The modifications exhibited important effect on enzyme activity and specificity against different glycopyranosides in the three cases. Physical modification showed a radical decrease in specific activity on all glycosidases, without any significant change in enzyme specificity toward monosaccharide (glucose or galactose) or glycoside (C-6 position free or phosphorylated). However, the surface covalent modification of the enzymes showed very interesting results. The glycosidase Lp_0440 showed low glycoside specificity at 25 °C, showing the same activity against p-nitrophenyl-glucopyranoside (pNP-Glu) or p-nitrophenyl-6-phosphate glucopyranoside (pNP-6P-Glu). However, the conjugated cHA-Lp_0440 showed a clear increase in the specificity towards the pNP-Glu and no activity against pNP-6P-Glu. The other two glycosidases (Lp_2777 and Lp_3525) showed high specificity towards pNP-6P-glycosides, especially to the glucose derivative. The HA covalent modification of Lp_3525 (cHA-Lp_3525) generated an enzyme completely specific against the pNP-6P-Glu (phosphoglycosidase) maintaining more than 80% of the activity after chemical modification. When the temperature was increased, an alteration of selectivity was observed. Lp_0440 and cHA-Lp_0440 only showed activity against p-nitrophenyl-galactopyranoside (pNP-Gal) at 40 °C, higher than at 25 °C in the case of the conjugated enzyme. ; This work was sponsored by the Spanish Government (Project No. AGL2017-84614-C2-2-R) and CSIC Project No. CSIC-PIE 201880E011). We also thank the Ministry of Education, Youth and Sports of the Community of Madrid and the European Social Fund for a contract to C.P.-R (PEJD-2017PRE/SAL-3762) in the program of Youth Employment and the Youth Employment Initiative (YEI) 2017. ; Peer reviewed

20 pags., 7 figs., 1 tab. ; Colorectal cancer pathogenesis and progression isassociated with the presence of Fusobacteriumnucleatum and the reduction of acetylated deriva-tives of spermidine, as well as dietary componentssuch as tannin-rich foods. We show that a new tan-nase orthologue of F. nucleatum (TanBFnn) has sig-nicant structural differences with its Lactobacillusplantarum counterpart affecting the ap covering theactive site and the accessibility of substrates. Crys-tallographic and molecular dynamics analysisrevealed binding of polyamines to a small cavity thatconnects the active site with the bulk solvent whichinteract with catalytically indispensable residues. Asa result, spermidine and its derivatives, particularlyN8-acetylated spermidine, inhibit the hydrolytic activ-ity of TanBFnnand increase the toxicity of gallotan-nins to F. nucleatum. Our results support a model inwhich the balance between the detoxicant activity ofTanBFnnand the presence of metabolic inhibitorscan dictate either conducive or unfavourable condi-tions for the survival of F. nucleatum. ; Supported by grants from the Spanish Ministry of Science and Innovation (MCI) cofinanced with FEDER funds (SAF2015‐65327‐R and RTI2018‐096494‐B‐100 to JA; AGL2017‐86757‐R to LA, SAF2015‐73549‐JIN to HR; RTI2018‐099592‐B‐C22 to GJO) and the Mizutani Foundation for Glycoscience (200077 to GJO). LA and GJO are supported by the Ramon y Cajal program (RYC‐2013‐13666 and RYC‐2013‐14706 respectively). JTC and AP are the recipients postdoctoral fellowships from the Basque Government. DB is the recipient of a MCI FPI fellowship. APC is the recipient of a fellowship from the University of the Basque Country. We thank the MCI for the Severo Ochoa Excellence accreditation (SEV‐2016‐0644) and the Basque Department of Industry, Tourism and Trade (Etortek and Elkartek programs). JMM thanks the ALBA synchrotron for providing access time to the BL‐13 XALOC beamline. This work is supported by grants from the Jesús de Gangoiti Barrera Foundation ; Peer reviewed

Gut microbiota is a constant source of antigens and stimuli to which the resident immune system has developed tolerance. However, the mechanisms by which mononuclear phagocytes, specifically monocytes/macrophages, cope with these usually pro-inflammatory signals are poorly understood. Here, we show that innate immune memory promotes anti-inflammatory homeostasis, using as model strains of the commensal bacterium Lactiplantibacillus plantarum. Priming of monocytes/macrophages with bacteria, especially in its live form, enhances bacterial intracellular survival and decreases the release of pro-inflammatory signals to the environment, with lower production of TNF and higher levels of IL-10. Analysis of the transcriptomic landscape of these cells shows downregulation of pathways associated with the production of reactive oxygen species (ROS) and the release of cytokines, chemokines and antimicrobial peptides. Indeed, the induction of ROS prevents memory-induced bacterial survival. In addition, there is a dysregulation in gene expression of several metabolic pathways leading to decreased glycolytic and respiratory rates in memory cells. These data support commensal microbe-specific metabolic changes in innate immune memory cells that might contribute to homeostasis in the gut. ; Supported by grants from the Spanish Ministry of Science, Innovation and Universities (MCIU) co-financed with FEDER funds (RTI2018-096494-B-100 to JA; BFU2016-76872-R to EB; AGL2017-86757-R to LA; SAF2015-73549-JIN to HR; SAF2016–77433-R and PID2019-110240RB-I00 to RPR). AP is supported by a Postdoctoral Fellowship from the Basque Government. DB and TMM are recipients of MCIU FPI fellowships. APC is a recipient of a fellowship from the University of the Basque Country. LA and RPR are supported by the Ramon y Cajal program from the Spanish Ministry of Economy and Competitiveness. We thank the MCIU for the Severo Ochoa Excellence accreditation (SEV-2016-0644), the Basque Department of Industry, Tourism and Trade (Etortek and Elkartek programs) and the Innovation Technology Department of the Bizkaia Province. This work was further supported by grants from the Jesús de Gangoiti Barrera Foundation. ; Peer reviewed