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1.
Int J Mol Sci ; 24(23)2023 Dec 02.
Article in English | MEDLINE | ID: mdl-38069394

ABSTRACT

Genome mining of Streptomyces exfoliatus DSMZ 41693 has allowed us to identify four different lipase-encoding sequences, and one of them (SeLipC) has been successfully cloned and extracellularly expressed using Rhodococcus sp. T104 as a host. SeLipC was purified by one-step hydrophobic interaction chromatography. The enzyme is a monomeric protein of 27.6 kDa, which belongs to subfamily I.7 of lipolytic enzymes according to its phylogenetic analysis and biochemical characterization. The purified enzyme shows the highest activity at 60 °C and an optimum pH of 8.5, whereas thermal stability is significantly improved when protein concentration is increased, as confirmed by thermal deactivation kinetics, circular dichroism, and differential scanning calorimetry. Enzyme hydrolytic activity using p-nitrophenyl palmitate (pNPP) as substrate can be modulated by different water-miscible organic cosolvents, detergents, and metal ions. Likewise, kinetic parameters for pNPP are: KM = 49.6 µM, kcat = 57 s-1, and kcat/KM = 1.15 × 106 s-1·M-1. SeLipC is also able to hydrolyze olive oil and degrade several polyester-type polymers such as poly(butylene succinate) (PBS), poly(butylene succinate)-co-(butylene adipate) (PBSA), and poly(ε-caprolactone) (PCL). Moreover, SeLipC can catalyze the synthesis of different sugar fatty acid esters by transesterification using vinyl laurate as an acyl donor, demonstrating its interest in different biotechnological applications.


Subject(s)
Lipase , Lipase/metabolism , Phylogeny , Enzyme Stability , Temperature
2.
Lancet Reg Health Eur ; 34: 100744, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37927430

ABSTRACT

Coverage of migrant and refugee data is incomplete and of insufficient quality in European health information systems. This is not because we lack the knowledge or technology. Rather, it is due to various political factors at local, national and European levels, which hinder the implementation of existing knowledge and guidelines. This reflects the low political priority given to the topic, and also complex governance challenges associated with migration and displacement. We review recent evidence, guidelines, and policies to propose four approaches that will advance science, policy, and practice. First, we call for strategies that ensure that data is collected, analyzed and disseminated systematically. Second, we propose methods to safeguard privacy while combining data from multiple sources. Third, we set out how to enable survey methods that take account of the groups' diversity. Fourth, we emphasize the need to engage migrants and refugees in decisions about their own health data. Based on these approaches, we propose a change management approach that narrows the gap between knowledge and action to create healthcare policies and practices that are truly inclusive of migrants and refugees. We thereby offer an agenda that will better serve public health needs, including those of migrants and refugees and advance equity in European health systems. Funding: No specific funding received.

3.
Prehosp Disaster Med ; 37(6): 827-831, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36189724

ABSTRACT

Once an emergency has passed, general attention typically returns to dealing with day-to-day system management, and the opportunity to learn from the crisis and improve is missed. Lessons from the coronavirus disease 2019 (COVID-19) crisis must be learned, and the necessary changes made at all levels, both in terms of improving collaboration and strengthening health systems. This special report provides the conclusion of a workshop held in the European Parliament (EP) in Brussels, Belgium. The event explored the modalities of response and preparation to the COVID-19 pandemic, and to health crises in general. The workshop considered actions at different levels: international organizations (global level), European Union (EU) Member States ([MS] national level), and health services (local level). It provided an opportunity to look back at several initiatives taken during the pandemic, and to draw inspiration from them.


Subject(s)
COVID-19 , Pandemics , Humans , COVID-19/epidemiology , Belgium
5.
AMB Express ; 12(1): 12, 2022 Feb 05.
Article in English | MEDLINE | ID: mdl-35122534

ABSTRACT

Cold-adapted filamentous fungal strain Geomyces sp. B10I has been reported to decompose polyesters such as poly(e-caprolactone) (PCL), poly(butylene succinate) (PBS) and poly(butylene succinate-co-butylene adipate) (PBSA). Here, we identified the enzymes of Geomyces sp. B10I, which appear to be responsible for its biodegradation activity. We compared their amino acid sequences with sequences of well-studied fungal enzymes. Partial purification of an extracellular mixture of the two enzymes, named hydrGB10I and chitGB10I, using ammonium sulfate precipitation and ionic exchange chromatography gave 14.16-fold purity. The amino acid sequence of the proteins obtained from the MALDI-TOF analysis determined the molecular mass of 77.2 kDa and 46.5 kDa, respectively. Conserved domain homology analysis revealed that both proteins belong to the class of hydrolases; hydrGB10I belongs to the glycosyl hydrolase 81 superfamily, while chitGB10I contains the domain of the glycosyl hydrolase 18 superfamily. Phylogenetic analysis suggests a distinct nature of the hydrGB10I and chitGB10I of Geomyces sp. B10I when compared with other fungal polyester-degrading enzymes described to date.

14.
Int J Biol Macromol ; 192: 138-150, 2021 Dec 01.
Article in English | MEDLINE | ID: mdl-34624379

ABSTRACT

Nucleoside 2'-deoxyribosyltransferases (NDTs) catalyze the cleavage of glycosidic bonds of 2'-deoxynucleosides and the following transfer of the 2'-deoxyribose moiety to acceptor nucleobases. Here, we report the crystal structures and biochemical properties of the first tetrameric NDTs: the type I NDT from the mesophilic bacterium Enterococcus faecalis V583 (EfPDT) and the type II NDT from the bacterium Desulfotalea psychrophila (DpNDT), the first psychrophilic NDT. This novel structural and biochemical data permitted an exhaustive comparative analysis aimed to shed light into the basis of the high global stability of the psychrophilic DpNDT, which has a higher melting temperature than EfPDT (58.5 °C versus 54.4 °C) or other mesophilic NDTs. DpNDT possesses a combination of unusual structural motifs not present neither in EfPDT nor any other NDT that most probably contribute to its global stability, in particular, a large aliphatic isoleucine-leucine-valine (ILV) bundle accompanied by a vicinal disulfide bridge and also an intersubunit disulfide bridge, the first described for an NDT. The functional and structural features of DpNDT do not fit the standard features of psychrophilic enzymes, which lead us to consider the implication of (sub)cellular levels together with the protein level in the adaptation of enzymatic activity to low temperatures.


Subject(s)
Bacterial Proteins/chemistry , Models, Molecular , Pentosyltransferases/chemistry , Protein Conformation , Protein Multimerization , Adaptation, Physiological , Bacterial Proteins/isolation & purification , Catalytic Domain , Chemical Phenomena , Cold Temperature , Disulfides , Enzyme Activation , Enzyme Stability , Pentosyltransferases/isolation & purification , Recombinant Proteins/chemistry , Recombinant Proteins/isolation & purification , Spectrum Analysis , Thermodynamics
15.
Antibiotics (Basel) ; 10(8)2021 Jul 29.
Article in English | MEDLINE | ID: mdl-34438972

ABSTRACT

Many intercellular communication processes, known as quorum sensing (QS), are regulated by the autoinducers N-acyl-l-homoserine lactones (AHLs) in Gram-negative bacteria. The inactivation of these QS processes using different quorum quenching (QQ) strategies, such as enzymatic degradation of the autoinducers or the receptor blocking with non-active analogs, could be the basis for the development of new antimicrobials. This study details the heterologous expression, purification, and characterization of a novel N-acylhomoserine lactone acylase from Actinoplanes utahensis NRRL 12052 (AuAHLA), which can hydrolyze different natural penicillins and N-acyl-homoserine lactones (with or without 3-oxo substitution), as well as synthesize them. Kinetic parameters for the hydrolysis of a broad range of substrates have shown that AuAHLA prefers penicillin V, followed by C12-HSL. In addition, AuAHLA inhibits the production of violacein by Chromobacterium violaceum CV026, confirming its potential use as a QQ agent. Noteworthy, AuAHLA is also able to efficiently synthesize penicillin V, besides natural AHLs and phenoxyacetyl-homoserine lactone (POHL), a non-natural analog of AHLs that could be used to block QS receptors and inhibit signal of autoinducers, being the first reported AHL acylase capable of synthesizing AHLs.

16.
Health Policy Series: 56;
Monography in English | WHO IRIS | ID: who-348493

ABSTRACT

COVID-19 has created huge challenges. The lessons it has generated on preparing for future pandemics are clear but they are by no means the only learning. All health systems are vulnerable and there are practical steps that all countries can take, not simply to increase the resources available, but to ensure the capacity to mobilize, adapt and use those resources in different shock scenarios. The Health systems resilience during COVID-19: Lessons for building back better study gathers the evidence of how countries have managed (or not managed) to re-engineer what they do, who does what and how, and draws out the implications for future resilience. The study understands resilience as the ability of the health system to prepare for, manage and learn from a sudden and extreme disturbance. It is about maintaining the performance of core heath system functions. While the focus here is on responding to shock, it is increasingly evident that the ability to transform and evolve will also be critical in meeting long-term structural challenges to health systems.


Subject(s)
Health Services , Delivery of Health Care , Emergencies , COVID-19 , Efficiency , Policy
17.
Bioresour Technol ; 307: 123258, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32247276

ABSTRACT

In this work, a mono- and a bi-enzymatic analytical immobilized enzyme reactors (IMERs) were developed as prototypes for biosynthetic purposes and their performances in the in-flow synthesis of nucleoside analogues of pharmaceutical interest were evaluated. Two biocatalytic routes based on nucleoside 2'-deoxyribosyltransferase from Lactobacillus reuteri (LrNDT) and uridine phosphorylase from Clostridium perfrigens (CpUP)/purine nucleoside phosphorylase from Aeromonas hydrophila (AhPNP) were investigated in the synthesis of 2'-deoxy, 2',3'-dideoxy and arabinonucleoside derivatives. LrNDT-IMER catalyzed the synthesis of 5-fluoro-2'-deoxyuridine and 5-iodo-2'-deoxyuridine in 65-59% conversion yield, while CpUP/AhPNP-IMER provided the best results for the preparation of arabinosyladenine (60% conversion yield). Both IMERs proved to be promising alternatives to chemical routes for the synthesis of nucleoside analogues. The developed in-flow system represents a powerful tool for the fast production on analytical scale of nucleosides for preliminary biological tests.


Subject(s)
Enzymes, Immobilized , Nucleosides , Biocatalysis , Pentosyltransferases , Purine-Nucleoside Phosphorylase
18.
Biochim Biophys Acta Proteins Proteom ; 1868(2): 140315, 2020 02.
Article in English | MEDLINE | ID: mdl-31740410

ABSTRACT

Application of polyester-degrading enzymes should be considered as an eco-friendly alternative to chemical recycling due to the huge plastic waste disposal nowadays. Many hydrolases from several fungi and bacteria have been discovered and successfully evaluated for their activity towards different aliphatic polyesters (PHA, PBS, PBSA, PCL, PLA), aromatic polyesters (PET, PBT, PMT) as well as their co-polyesters (PBST, PBAT, PBSTIL). This revision gives an up-to-date overview on the main biochemical features and biotechnological applications of those reported enzymes which are able to degrade polyester-based plastics, including different microbial polyester depolymerases, esterases, cutinase-like enzymes and lipases. Summarized information includes available protein sequences with the corresponding accession numbers deposited in NCBI server, 3D resolved structures, and data about optimal conditions for enzymatic activity and stability of many of these microbial enzymes that would be helpful for researchers in this topic. Although screening and identification of new native polyester hydrolases from microbial sources is undeniable according to literature, we briefly highlight the importance of the design of improved enzymes towards recalcitrant aromatic polyesters through different approaches that include site-directed mutagenesis and surface protein engineering.


Subject(s)
Bacterial Proteins/metabolism , Biodegradable Plastics/metabolism , Carboxylic Ester Hydrolases/metabolism , Lipase/metabolism , Polyesters/metabolism , Bacteria/enzymology , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Biodegradable Plastics/chemistry , Carboxylic Ester Hydrolases/chemistry , Carboxylic Ester Hydrolases/genetics , Catalytic Domain , Lipase/chemistry , Lipase/genetics , Polyesters/chemistry , Protein Engineering
19.
Appl Microbiol Biotechnol ; 99(22): 9605-15, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26156240

ABSTRACT

Cloning and biochemical characterization of a novel extracellular medium-chain-length polyhydroxyalkanoate (mcl-PHA) depolymerase from Streptomyces exfoliatus K10 DSMZ 41693 are described. The primary structure of the depolymerase (PhaZSex2) includes the lipase consensus sequence (serine-histidine-aspartic acid) which is known for serine hydrolases. Secondary structure analysis shows 7.9 % α-helix, 43.9 % ß-sheet, 19.4 % ß-turns, and 31.2 % random coil, suggesting that this enzyme belongs to the α/ß hydrolase fold family, in agreement with other PHA depolymerases and lipases. The enzyme was efficiently produced as an extracellular active form in Rhodococcus and purified by two consecutive hydrophobic chromatographic steps. Matrix-assisted laser desorption-time-of-flight (MALDI-TOF) analysis of the purified enzyme revealed a monomer of 27.6 kDa with a midpoint transition temperature of 44.2 °C. Remarkably, the activity is significantly enhanced by low concentrations of nonionic and anionic detergents and thermal stability is improved by the presence of 10 % glycerol. PhaZSex2 is an endo-exohydrolase that cleaves both large and small PHA molecules, producing (R)-3-hydroxyoctanoic acid monomers as the main reaction product. Markedly, PhaZSex2 is able to degrade functionalized polymers containing thioester groups in the side chain (PHACOS), releasing functional thioester-based monomers and oligomers demonstrating the potentiality of this novel biocatalyst for the industrial production of enantiopure (R)-3-hydroxyalkanoic acids.


Subject(s)
Carboxylic Ester Hydrolases/genetics , Carboxylic Ester Hydrolases/metabolism , Polyhydroxyalkanoates/metabolism , Streptomyces/enzymology , Biotransformation , Carboxylic Ester Hydrolases/chemistry , Carboxylic Ester Hydrolases/isolation & purification , Cloning, Molecular , Enzyme Stability , Gene Expression , Molecular Weight , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Rhodococcus/genetics , Rhodococcus/metabolism , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Streptomyces/genetics , Substrate Specificity , Temperature
20.
Am J Hematol ; 90(5): 429-33, 2015 May.
Article in English | MEDLINE | ID: mdl-25683327

ABSTRACT

The role of bosutinib as rescue treatment of Philadelphia chromosome-positive chronic myeloid leukemia (CML) patients after failing three previous tyrosine kinase inhibitors (TKIs) is currently unknown. We report here the largest series (to our knowledge) of patients treated with bosutinib in fourth-line, after retrospectively reviewing 30 patients in chronic phase, and pretreated with imatinib, nilotinib, and dasatinib. With a median follow up of 11.1 months, the probability to either maintain or improve their CCyR response was 56.6% (17/30) and 11 patients (36.7%) achieved or maintained their baseline MMR. In patients not having baseline CCyR, the probabilities of obtaining CCyR, MMR, and MR4.5 were 13, 11, and 14%, respectively. The probabilities of obtaining MMR and deep molecular response MR4.5 in patients with baseline CCyR were 40.0% (6/15) and 20.0% (3/15). At 20 months, progression-free survival was 73%. Grade 3-4 hematological toxicities were more frequent in resistant than intolerant patients (45.4 vs. 0.0%). Nonhematological toxicities were also more frequent in resistant patients, being diarrhea the most conspicuous one. Bosutinib seems to be an appropriate treatment option for patients resistant or intolerant to three prior TKI's.


Subject(s)
Aniline Compounds/therapeutic use , Antineoplastic Agents/therapeutic use , Compassionate Use Trials , Leukemia, Myeloid, Chronic-Phase/drug therapy , Nitriles/therapeutic use , Protein Kinase Inhibitors/therapeutic use , Quinolines/therapeutic use , Adult , Aged , Benzamides/therapeutic use , Dasatinib , Drug Resistance, Neoplasm , Female , Humans , Imatinib Mesylate , Leukemia, Myeloid, Chronic-Phase/enzymology , Leukemia, Myeloid, Chronic-Phase/mortality , Leukemia, Myeloid, Chronic-Phase/pathology , Male , Middle Aged , Piperazines/therapeutic use , Protein-Tyrosine Kinases/antagonists & inhibitors , Protein-Tyrosine Kinases/metabolism , Pyrimidines/therapeutic use , Retrospective Studies , Spain , Survival Analysis , Thiazoles/therapeutic use
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