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1.
Physiol Behav ; 283: 114602, 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38851442

ABSTRACT

Muscle testing is an integral component in assessing musculoskeletal function and tailoring rehabilitation efforts. This study aimed i. to identify an objective evaluation system sensitive to analyze changes in different muscular conditions in different neuromuscular tests across a spectrum of professional experience levels; and ii. to analyze differences in objective parameters and clinical judgment between participants of different levels of expertise in different muscular conditions in different neuromuscular tests. Participants included 60 subjects with Level I to III expertise who performed blinded neuromuscular tests on the middle deltoid and rectus femoris muscles of 40 volunteer subjects. The methodology centered on standardizing test protocols to minimize variability, employing EMG to quantify muscle activity, thermography to capture thermographic muscular response, and digital dynamometry to measure muscular resistance. The findings revealed that while traditional methods like thermography and electromyography provide valuable insights, digital dynamometry stands out for its sensitivity in detecting muscle condition changes in neuromuscular test. Moreover, the data underscored the pivotal role of advanced training and expertise in enhancing the precision and accuracy of neuromuscular diagnostics, since there were significant differences in objective parameters and clinical judgment between participants of different levels of expertise in the different muscular conditions in Middle deltoid and Rectus femoris neuromuscular tests analyzed, presenting higher expertise participant clinical judgment like objective validated instrument.

2.
Int J Biol Macromol ; 242(Pt 3): 124968, 2023 Jul 01.
Article in English | MEDLINE | ID: mdl-37217044

ABSTRACT

Lignin modifying enzymes (LMEs) have gained widespread recognition in depolymerization of lignin polymers by oxidative cleavage. LMEs are a robust class of biocatalysts that include lignin peroxidase (LiP), manganese peroxidase (MnP), versatile peroxidase (VP), laccase (LAC), and dye-decolorizing peroxidase (DyP). Members of the LMEs family act on phenolic, non-phenolic substrates and have been widely researched for valorization of lignin, oxidative cleavage of xenobiotics and phenolics. LMEs implementation in the biotechnological and industrial sectors has sparked significant attention, although its potential future applications remain underexploited. To understand the mechanism of LMEs in sustainable pollution mitigation, several studies have been undertaken to assess the feasibility of LMEs in correlating to diverse pollutants for binding and intermolecular interactions at the molecular level. However, further investigation is required to fully comprehend the underlying mechanism. In this review we presented the key structural and functional features of LMEs, including the computational aspects, as well as the advanced applications in biotechnology and industrial research. Furthermore, concluding remarks and a look ahead, the use of LMEs coupled with computational framework, built upon artificial intelligence (AI) and machine learning (ML), has been emphasized as a recent milestone in environmental research.


Subject(s)
Artificial Intelligence , Lignin , Lignin/chemistry , Peroxidases/metabolism , Biotechnology , Laccase , Phenols
3.
Int J Mol Sci ; 24(5)2023 Feb 24.
Article in English | MEDLINE | ID: mdl-36901905

ABSTRACT

Nowadays, the worldwide demand for Active Pharmaceutical Ingredients (APIs) requires novel, cost-effective, safe, and environmentally friendly synthetic processes [...].


Subject(s)
Biocatalysis , Pharmaceutical Preparations
4.
Mar Drugs ; 21(2)2023 Jan 29.
Article in English | MEDLINE | ID: mdl-36827140

ABSTRACT

The use of marine enzymes as catalysts for biotechnological applications is a topical subject. Marine enzymes usually display better operational properties than their animal, plant or bacterial counterparts, enlarging the range of possible biotechnological applications. Due to the fact that cytochrome P450 enzymes can degrade many different toxic environmental compounds, these enzymes have emerged as valuable tools in bioremediation processes. The present work describes the isolation, purification and biochemical characterization of a liver NADPH-dependent cytochrome P450 reductase (CPR) from the marine fish Liza klunzingeri (LkCPR). Experimental results revealed that LkCPR is a monomer of approximately 75 kDa that is active in a wide range of pH values (6-9) and temperatures (40-60 °C), showing the highest catalytic activity at pH 8 and 50 °C. The activation energy of the enzyme reaction was 16.3 kcal mol-1 K-1. The KM values for cytochrome C and NADPH were 8.83 µM and 7.26 µM, and the kcat values were 206.79 s-1 and 202.93 s-1, respectively. LkCPR displayed a specific activity versus cytochrome C of 402.07 µmol min-1 mg1, the highest activity value described for a CPR up to date (3.2-4.7 times higher than the most active reported CPRs) and showed the highest thermostability described for a CPR. Taking into account all these remarkable catalytic features, LkCPR offers great potential to be used as a suitable biocatalyst.


Subject(s)
Cytochromes c , NADPH-Ferrihemoprotein Reductase , Animals , NADP , NADPH-Ferrihemoprotein Reductase/chemistry , NADPH-Ferrihemoprotein Reductase/metabolism , Liver/metabolism , Cytochrome P-450 Enzyme System
5.
Int J Biol Macromol ; 227: 535-550, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36516934

ABSTRACT

In recent decades, enzyme-based biocatalytic systems have garnered increasing interest in industrial and applied research for catalysis and organic chemistry. Many enzymatic reactions have been applied to sustainable and environmentally friendly production processes, particularly in the pharmaceutical, fine chemicals, and flavor/fragrance industries. However, only a fraction of the enzymes available has been stepped up towards industrial-scale manufacturing due to low enzyme stability and challenging separation, recovery, and reusability. In this context, immobilization and co-immobilization in robust support materials have emerged as valuable strategies to overcome these inadequacies by facilitating repeated or continuous batch operations and downstream processes. To further reduce separations, it can be advantageous to use multiple enzymes at once in one pot. Enzyme co-immobilization enables biocatalytic synergism and reusability, boosting process efficiency and cost-effectiveness. Several studies on multi-enzyme immobilization and co-localization propose kinetic advantages of the enhanced turnover number for multiple enzymes. This review spotlights recent progress in developing versatile biocatalytic cascade systems by multi-enzyme co-immobilization on environmentally friendly biopolymers and nanostructured materials and their application scope in the chemical and biotechnological industries. After a succinct overview of carrier-based and carrier-free immobilization/co-immobilizations, co-immobilization of enzymes on a range of biopolymer and nanomaterials-based supports is thoroughly compiled with contemporary and state-of-the-art examples. This study provides a new horizon in developing effective and innovative multi-enzymatic systems with new possibilities to fully harness the adventure of biocatalytic systems.


Subject(s)
Enzymes, Immobilized , Nanostructures , Enzymes, Immobilized/metabolism , Biocatalysis , Biopolymers , Enzyme Stability
6.
Int J Mol Sci ; 23(21)2022 Nov 07.
Article in English | MEDLINE | ID: mdl-36362425

ABSTRACT

Enzyme-mediated processes have proven to be a valuable and sustainable alternative to traditional chemical methods. In this regard, the use of multi-enzymatic systems enables the realization of complex synthetic schemes, while also introducing a number of additional advantages, including the conversion of reversible reactions into irreversible processes, the partial or complete elimination of product inhibition problems, and the minimization of undesirable by-products. In addition, the immobilization of biocatalysts on magnetic supports allows for easy reusability and streamlines the downstream process. Herein we have developed a cascade system for cladribine synthesis based on the sequential action of two magnetic biocatalysts. For that purpose, purine 2'-deoxyribosyltransferase from Leishmania mexicana (LmPDT) and Escherichia coli hypoxanthine phosphoribosyltransferase (EcHPRT) were immobilized onto Ni2+-prechelated magnetic microspheres (MagReSyn®NTA). Among the resulting derivatives, MLmPDT3 (activity: 11,935 IU/gsupport, 63% retained activity, operational conditions: 40 °C and pH 5-7) and MEcHPRT3 (12,840 IU/gsupport, 45% retained activity, operational conditions: pH 5-8 and 40-60 °C) emerge as optimal catalysts for further synthetic application. Moreover, the MLmPDT3/MEcHPRT3 system was biochemically characterized and successfully applied to the one-pot synthesis of cladribine under various conditions. This methodology not only displayed a 1.67-fold improvement in cladribine synthesis (compared to MLmPDT3), but it also implied a practically complete transformation of the undesired by-product into a high-added-value product (90% conversion of Hyp into IMP). Finally, MLmPDT3/MEcHPRT3 was reused for 16 cycles, which displayed a 75% retained activity.


Subject(s)
Cladribine , Enzymes, Immobilized , Enzymes, Immobilized/chemistry , Pentosyltransferases , Magnetics , Escherichia coli , Magnetic Phenomena
7.
Int J Mol Sci ; 23(19)2022 Oct 05.
Article in English | MEDLINE | ID: mdl-36233108

ABSTRACT

One of the major drawbacks of the industrial implementation of enzymatic processes is the low operational stability of the enzymes under tough industrial conditions. In this respect, the use of thermostable enzymes in the industry is gaining ground during the last decades. Herein, we report a structure-guided approach for the development of novel and thermostable 2'-deoxyribosyltransferases (NDTs) based on the computational design of disulfide bonds on hot spot positions. To this end, a small library of NDT variants from Lactobacillus delbrueckii (LdNDT) with introduced cysteine pairs was created. Among them, LdNDTS104C (100% retained activity) was chosen as the most thermostable variant, displaying a six- and two-fold enhanced long-term stability when stored at 55 °C (t1/255 °C ≈ 24 h) and 60 °C (t1/260 °C ≈ 4 h), respectively. Moreover, the biochemical characterization revealed that LdNDTS104C showed >60% relative activity across a broad range of temperature (30−90 °C) and pH (5−7). Finally, to study the potential application of LdNDTS104C as an industrial catalyst, the enzymatic synthesis of nelarabine was successfully carried out under different substrate conditions (1:1 and 3:1) at different reaction times. Under these experimental conditions, the production of nelarabine was increased up to 2.8-fold (72% conversion) compared with wild-type LdNDT.


Subject(s)
Enzymes, Immobilized , Pentosyltransferases , Arabinonucleosides , Cysteine , Disulfides/chemistry , Enzyme Stability , Enzymes, Immobilized/chemistry , Pentosyltransferases/metabolism , Substrate Specificity , Temperature
8.
Article in English | MEDLINE | ID: mdl-36294217

ABSTRACT

An anticipatory stress response develops before an internal or external stimulus, which initiates a homeostasis process through a chain of responses that enable human organisms to face different threats, thus allowing them to adapt to a continuous and eliciting environment. In the current research, we analyzed the psychophysiological anticipatory anxiety response of professional soldiers prior to a real mission in an actual theater of operation. Autonomic modulation through the heart rate variability values, muscular strength manifestation, and psychological stress of 53 military personnel of Army Airmobile Forces (age: M = 35.4 years, SD = 5.88 years; height: M = 1.75 m, SD = 6.87 cm; body mass: M = 77.33 kg, SD = 11.95 kg; military duty = 14.44 years, SD = 6.43; military operation experience = 4 months, SD = 4.25 months) and a control group of 33 civil participants were analyzed. The military personnel presented significant differences in some HRV values related to the activation of sympathetic systems. We found that the military personnel presented an anticipatory anxiety response only at an autonomic level, showing an increased sympathetic modulation, but not at a psychological level, since their anxiety levels were not significantly different than those of the control civilians. In addition, this anticipatory anxiety response did not affect muscular strength manifestation, as it presented no significant differences between the military personnel and the control group.


Subject(s)
Military Personnel , Humans , Adult , Military Personnel/psychology , Stress, Psychological , Anxiety , Autonomic Nervous System , Muscle Strength/physiology
9.
Methods Mol Biol ; 2397: 19-32, 2022.
Article in English | MEDLINE | ID: mdl-34813057

ABSTRACT

Droplet microfluidics enables the ultrahigh-throughput screening of the natural or man-made genetic diversity for industrial enzymes, with reduced reagent consumption and lower costs than conventional robotic alternatives. Here we describe an example of metagenomic screening for nucleoside 2'-deoxyribosyl transferases using FACS as a more widespread and accessible alternative than microfluidic on-chip sorters. This protocol can be easily adapted to directed evolution libraries by replacing the library construction steps and to other enzyme activities, e.g., oxidases, by replacing the proposed coupled assay.


Subject(s)
High-Throughput Screening Assays , Microfluidics , Humans , Metagenome , Metagenomics
10.
Biomed Res Int ; 2021: 6633851, 2021.
Article in English | MEDLINE | ID: mdl-34853792

ABSTRACT

There is a lack of information on the psychophysiological response of pilots under hypoxic conditions. The study of the physiological, psychological, cardiorespiratory, neurological, behavioural, sensory, and cognitive symptoms that may appear during training in hypobaric chambers is essential to optimize the training processes of aircrew members. Thus, the present study is aimed at analyzing the psychophysiological responses of aircrew members in an incremental hypoxia training protocol. Psychophysiological responses of 44 aircrew members (34 males and 10 females) in an incremental hypoxia training protocol (3 minutes at 0 meters, 8 minutes at 5,000 meters, and maximum time at 7500 meters) were measured. Results suggested that the incremental hypoxia training protocol did not affect cortical arousal and handgrip strength; however, it increased the sympathetic tone, perceived stress, perceived effort, and heart rate and decreased forced expiratory volume and blood oxygen saturation. Thus, we concluded that acute hypoxic hypobaric exposure leads to decreased parasympathetic tone, blood oxygen saturation, and maximal spirometry values, without negatively affecting handgrip strength and cortical arousal. This information will lead to find specific training systems that meet the real needs of aircrew.


Subject(s)
Altitude Sickness/physiopathology , Altitude Sickness/psychology , Pilots/psychology , Adult , Aerospace Medicine , Aircraft , Atmospheric Pressure , Female , Hand Strength , Humans , Male , Middle Aged , Oxygen Saturation , Parasympathetic Nervous System/physiopathology , Psychophysiology , Respiratory Function Tests , Stress, Physiological , Stress, Psychological
11.
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
13.
Bioresour Technol ; 339: 125649, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34329899

ABSTRACT

Nowadays, enzymatic synthesis of nucleotides is an efficient and sustainable alternative to chemical methodologies. In this regard, after the biochemical characterization of wild-type and mutant uracil phosphoribosyltransferases from Toxoplasma gondii (TgUPRT, TgUPRT2, and TgUPRT3), TgUPRT2 was selected as the optimal candidate (69.5 IU mg-1, UMP synthesis) for structure-guided immobilization onto Ni2+ chelate (MNiUPRT2) and onto glutaraldehyde-activated microparticles (MGlUPRT2). Among resulting derivatives, MNiUPRT23 (6127 IU g-1biocat; 92% retained activity; 3-5 fold enhanced stability at 50-60 °C) and MGlUPRT2N (3711 IU g-1biocat; 27% retained activity; 8-20 fold enhanced stability at 50-60 °C) displayed the best operability. Moreover, the enzymatic synthesis of different pyrimidine NMPs was performed. Finally, the reusability of both derivatives in 5-FUMP synthesis (MNiUPRT23, 80% retained activity after 7 cycles, 5 min; MGlUPRT2N, 70% retained activity after 10 cycles, 20 min) was carried out at short times.


Subject(s)
Pyrimidine Nucleosides , Toxoplasma , Nucleotides , Pentosyltransferases/genetics , Toxoplasma/genetics
14.
Physiol Behav ; 238: 113489, 2021 09 01.
Article in English | MEDLINE | ID: mdl-34097974

ABSTRACT

Present research studied the psychophysiological response and shooting performance taking into consideration the experience of the soldier after a physical stress protocol, which leaded to acute fatigue conditions. Sixty soldiers were divided into experienced and non-experienced groups to conduct a high-intensity interval training (HIIT) based on endurance type exercises (10 intervals of 40 m run at maximum intensity with 2 changes of direction and 45 s of recovery. Psychophysiological and shooting performance variables were measured before, during and after the HIIT protocol. Significant increases in heart rate, blood lactate, lower limbs strength, as well as a significant decrease in blood oxygen saturation and body temperature were found in both groups. Shooting performance was affected by experience and fatigue, being more accentuated in non-experienced. Present HIIT protocol elicited a similar psychophysiological response than in previously reported combat manoeuvres, thus proving to be an optimal stimuli approach/intervention for soldier's specific physical preparation.


Subject(s)
High-Intensity Interval Training , Military Personnel , Fatigue , Heart Rate , Humans , Stress, Physiological
15.
Biotechnol Adv ; 51: 107782, 2021 11 01.
Article in English | MEDLINE | ID: mdl-34062245
16.
Biomolecules ; 11(5)2021 04 29.
Article in English | MEDLINE | ID: mdl-33947162

ABSTRACT

Nowadays, enzyme-mediated processes offer an eco-friendly and efficient alternative to the traditional multistep and environmentally harmful chemical processes. Herein we report the enzymatic synthesis of cladribine by a novel 2'-deoxyribosyltransferase (NDT)-based combined biocatalyst. To this end, Lactobacillus delbrueckii NDT (LdNDT) was successfully immobilized through a two-step immobilization methodology, including a covalent immobilization onto glutaraldehyde-activated biomimetic silica nanoparticles followed by biocatalyst entrapment in calcium alginate. The resulting immobilized derivative, SiGPEI 25000-LdNDT-Alg, displayed 98% retained activity and was shown to be active and stable in a broad range of pH (5-9) and temperature (30-60 °C), but also displayed an extremely high reusability (up to 2100 reuses without negligible loss of activity) in the enzymatic production of cladribine. Finally, as a proof of concept, SiGPEI 25000-LdNDT-Alg was successfully employed in the green production of cladribine at mg scale.


Subject(s)
Cladribine/metabolism , Lactobacillus delbrueckii/enzymology , Transferases/chemistry , Transferases/metabolism , Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , Biocatalysis , Enzyme Stability , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Glutaral/chemistry , Green Chemistry Technology , Hydrogen-Ion Concentration , Silicon Dioxide/chemistry , Temperature
17.
Colloids Surf B Biointerfaces ; 203: 111747, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33839476

ABSTRACT

Fenneropenaeus merguiensis (commonly named banana shrimp) is one of the most important farmed crustacean worldwide species for the fisheries and aquaculture industry. Besides its nutritional value, it is a good source of chitinase, an enzyme with excellent biological and catalytic properties for many industrial applications. In the present study, a putative chitinase-encoding cDNA was synthesized from mRNA from F. merguiensis hepatopancreas tissue. Subsequently, the corresponding cDNA was cloned, sequenced and functionally expressed in Escherichia coli, and the recombinant F. merguiensis chitinase (rFmCHI) was purified by His-tag affinity chromatography. The bioinformatics analysis of aminoacid sequence of rFmCHI displayed a cannonical multidomain architecture in chitinases which belongs to glycoside hydrolase family 18 (GH18 chitinase). Biochemical characterization revealed rFmCHI as a monomeric enzyme of molecular weight 52 kDa with maximum activity at 40 °C and pH 6.0 Moreover, the recombinant enzyme is also stable up to 60 °C, and in the pH range 5.0-8.0. Steady-state kinetic studies for colloidal chitin revealed KM, Vmax and kcat values of 78.18 µM, 0.07261 µM. min-1 and 43.37 s-1, respectively. Overall, our results aim to demonstrate the potential of rFmCHI as suitable catalyst for bioconversion of chitin waste.


Subject(s)
Chitinases , Amino Acid Sequence , Animals , Arthropod Proteins , Base Sequence , Chitin , Chitinases/genetics , Chitinases/metabolism , Kinetics , Penaeidae/enzymology
18.
Article in English | MEDLINE | ID: mdl-33917827

ABSTRACT

The actual COVID-19 pandemic scenario has generated a context of uncertainty, helplessness, and inequality. Yet, the perception of COVID-19 risk has influenced nutritional, psychological, and physical activity patterns depending on gender. We conducted the present research with the aim of studying gender differences of university students in the perceived risk of the COVID-19 pandemic, and in psychological, nutritional, oral health, and physical activity habits. To reach the study's aim, 300 volunteer university students completed an online questionnaire which analyzed variables of perceived risk of the COVID-19 pandemic, psychological profiles, and nutritional, oral health, and physical activity habits. Results showed that females presented a higher perception of danger to the COVID-19 virus than males but showed no differences in how the pandemic has affected personal lives. Females showed higher values of anxiety, conscientiousness, neuroticism, and openness to experience, while males presented higher values of extraversion. Nutritionally, males presented greater consumption of soft drinks, meat, and pasta or rice, and lower buccal hygiene. Yet, no differences were found regarding physical activity patterns. Results from the present study could be used by various educational institutions to implement multidisciplinary interventions to reduce the stress and risk perception.


Subject(s)
COVID-19 , Pandemics , Female , Humans , Male , Perception , SARS-CoV-2 , Sex Characteristics , Students , Universities
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