Implementation of an Algorithm for Testing, Diagnosis, and Antibiotic Stewardship of Asymptomatic Bacteriuria in Pregnancy.

BACKGROUND: Asymptomatic bacteriuria (ASB) affects 2-15% of pregnant women, with 20-40% developing symptoms later. Symptomatic urinary tract infections (UTIs) are more common in pregnancy, with a prevalence of 33%, posing risks like preterm delivery, low birth weight, and maternal pyelonephritis. The gold standard for UTI detection is a urine culture, but point-of-care urinalysis dipsticks are frequently performed as screens during regular obstetric visits. Leukocyte esterase has been used to justify treatment in the asymptomatic, even with low sensitivity and specificity. Confirmatory tests are crucial to avoid false positives and ensure optimal outcomes. Current guidelines for urinalysis dipstick interpretation and the decision to treat ASB in pregnancy are limited. It remains unclear if an evidence-based algorithm can improve test utilization, diagnosis, and treatment decisions for ASB in pregnancy. OBJECTIVES: The primary objective of our study is to develop, implement, and evaluate an evidence-based algorithm to guide urinalysis interpretation, culturing, diagnosis, and antibiotic stewardship of asymptomatic bacteriuria in pregnant patients during routine obstetric visits. STUDY DESIGN: The project involves both retrospective and quasi-experimental prospective chart reviews of pregnant patients aged 18 and older, beyond 20 weeks gestation, from routine obstetric visits with urinalysis dipstick tests. A doctorate in clinical laboratory sciences student developed an educational algorithm to guide urinalysis dipstick interpretation, culturing necessity, and treatment decisions based on evidence-based practice. Our study considered patient records from February 1 - 28, 2022 as retrospective (pre-algorithm implementation) data and January 24 - February 22, 2023, as prospective (post-algorithm implementation) data. Data collected from the electronic medical record included de-identified patient information, urinalysis results, culture dates and outcomes, antibiotic prescriptions, UTI or ASB diagnoses, provider details, adverse pregnancy outcomes, and demographics. Data analysis using SPSS version 29 involved chi-square tests, likelihood ratios, and effect size calculations, with P-values <0.05 considered statistically significant. RESULTS: In our study, we examined a total of 1,176 patient records. Pre-implementation data included 440 records, with 224 abnormal and 216 normal urinalyses. Post-implementation data encompassed 736 records, of which 255 were abnormal and 481 were normal. The patient demographics predominantly featured White (87%), with a median maternal age of 27 years and a gestational age of 32 weeks. Our pre-implementation analyses revealed significant associations between algorithm deviations with both culture utilization (P <.001) and antibiotic stewardship (P <.001). However, no significant associations were observed between algorithm deviations and adverse patient outcomes. Culture underutilization decreased significantly from 43.0% (189/440) pre-implementation to 29.5% (217/736) post-implementation (P < .001). The overall reduction in ASB prevalence from 16.3% (8/49) to 6.7% (10/67) suggests a decrease of nearly 60%. Additionally, antibiotic overprescription decreased significantly from 1.6% (4/258) pre-implementation to 0.8% (4/522) post-implementation (P = .003), with a reduction from 7.1% (3/42) to 2.4% (1/41) among abnormal urinalyses. CONCLUSION: Our findings show a strong alignment between the use of the algorithm and subsequent clinical decisions, underscoring its potential to enhance patient care and management in obstetric settings. Notably, adherence to the algorithm was higher among providers displaying prudent antibiotic use.

Distinct Adjacent Substrate Binding Pocket Regulates the Activity of a Decameric Feruloyl Esterase from Bacteroides thetaiotaomicron.

Understanding how the human gut microbiota contribute to the metabolism of dietary carbohydrates is of great interest, particularly those with ferulic acid (FA) decorations that have manifold health benefits. Here, we report the crystal structure of a decameric feruloyl esterase (BtFae) from Bacteroides thetaiotaomicron in complex with methyl ferulate (MFA), revealing that MFA is situated in a noncatalytic substrate binding pocket adjacent to the catalytic pocket. Molecular docking and mutagenesis studies further demonstrated that the adjacent pocket affects substrate binding in the active site and negatively regulates the BtFae activity on both synthetic and natural xylan substrates. Additionally, quantum mechanics (QM) calculations were employed to investigate the catalytic process of BtFae from substrate binding to product release, and identified TS_2 in the acylation step is rate-limiting. Collectively, this study unmasks a novel regulatory mechanism of FAE activity, which may contribute to further investigation of FA-conjugated polysaccharides metabolism in the human gut.

Synthesis and release studies on amylose-based ester prodrugs of fenamic acid NSAIDs.

Aim: To achieve colon-targeted release of mefenamic acid from its ester-linked amylose prodrugs.Materials & methods: The prodrug was characterized by 1H NMR and IR spectroscopy. Drug activation and release profile was studied in enzyme enriched simulated physiological media via UV-vis spectroscopy and was validated with HPLC analysis. ELISA assay was employed for evaluating the % inhibition of COX-1 and COX-2 inhibition at different concentrations of the prodrug preincubated with ester and/ or amylose hydrolyzing enzymes. SEM studies further validated the performance of the prodrug under simulated physiological conditions.Results: Pancreatin was essential for the prodrug activation in SIM to make the ester bonds in prodrug vulnerable to hydrolysis by esterase. This evidence was confirmed by drug release studies, HPLC analysis, ELISA assay and SEM investigation where the ester conjugated prodrug showed marked stability in physiological media only to get activated in the presence of amylose degrading enzyme.Conclusion: Ester linked amylose-mefenamic acid conjugate showed both enzyme responsive activation and release in SIM.

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Novel Feruloyl Esterase for the Degradation of Polyethylene Terephthalate (PET) Screened from the Gut Microbiome of Plastic-Degrading Mealworms (Tenebrio Molitor Larvae).

Mealworms (Tenebrio molitor) larvae can degrade both plastics and lignocellulose through synergistic biological activities of their gut microbiota because they share similarities in chemical and physical properties. Here, a total of 428 genes encoding lignocellulose-degrading enzymes were screened from the gut microbiome of T. molitor larvae to identify poly(ethylene terephthalate) (PET)-degrading activities. Five genes were successfully expressed in E. coli, among which a feruloyl esterase-like enzyme named TmFae-PETase demonstrated the highest PET degradation activity, converting PET into MHET (0.7 mgMHETeq ·h-1·mgenzyme-1) and TPA (0.2 mgTPAeq ·h-1·mgenzyme-1) at 50 °C. TmFae-PETase showed a preference for the hydrolysis of ferulic acid methyl ester (MFA) in the presence of both PET and MFA. Site-directed mutagenesis and molecular dynamics simulations of TmFae-PETase revealed similar catalytic mechanisms for both PET and MFA. TmFae-PETase effectively depolymerized commercial PET, making it a promising candidate for application. Additionally, the known PET hydrolases IsPETase, FsC, and LCC also hydrolyzed MFA, indicating a potential origin of PET hydrolytic activity from its lignocellulosic-degrading abilities. This study provides an innovative strategy for screening PET-degrading enzymes identified from lignocellulose degradation-related enzymes within the gut microbiome of plastic-degrading mealworms. This discovery expands the existing pool of plastic-degrading enzymes available for resource recovery and bioremediation applications.

Fabrication of hydrogen-bonded crosslinked hydrogel vitrimer with enhanced self-healing and printability via K+ induced low methyl apple pectin.

Low methyl pectin, conventionally extruded as sols and shaped through Ca2+ post-curing, face complexity and high production costs, limiting their application in 3D printing. We developed apple pectin (AP) vitrimer inks with shear-thinning behavior at elevated temperatures and self-supporting properties at low ones, via pectin methyl esterase (PME) modification and K+ induction, aiming to facilitate simpler extrusion 3D printing. PME-modified AP (PME-AP) exhibits a higher affinity for K+ compared to AP, attributed to an 8.76 % reduction in the degree of methyl esterification and a 9.72 % increase in the degree of blockiness. Consequently, 1 % PME-AP forms a robust hydrogel vitrimer characterized by a hardness of 121.33 g and a water holding capacity of 99.50 % at 150 mM K+, a 68 % reduction in K+ concentration requirement over AP gels. Through electrostatic shielding, K+ induces hydrogen-bonded crosslinked vitrimers with stress relaxation within 53 s at 80 °C and self-healing properties with minimal texture reduction (~2 g). These characteristics suggest that the hydrogen bond crosslinked vitrimer network can dynamically reorganize in response to temperature variations, making PME-AP gel ideal for 3D printing applications. This study establishes the groundwork for cost-efficient AP-based extrusion 3D printing.

Recombinant Esterase (BaCEm) Immobilized on Polyethyleneimine-Impregnated Mesoporous Silica SBA-15 Exhibits Outstanding Catalytic Performance.

A recombinant esterase, BaCEm, derived from Bacillus aryabhattai and heterologously expressed in Escherichia coli, was successfully immobilized on polyethyleneimine-impregnated mesoporous silica SBA-15. This immobilization utilized glutaraldehyde as a crosslinker. Optimal conditions were established with a PEI/SBA-15 ratio of 25% (w/w), a pH of 7.5, and a glutaraldehyde concentration of 0.5% (w/w), resulting in a loading capacity of 76.4 mg/g, a recovery activity of 43.5%, and a specific activity of 7917 U/g for BaCEm. The immobilized BaCEm demonstrated high enantioselectivity, with an "E" value of 203.92, in the resolution assay of (R,S)-ethyl indoline-2-carboxylate. Notably, the immobilized enzyme, compared to its free counterpart, exhibited enhanced thermostability, maintaining 95.4% of its activity after 3 h at 30 °C. It also showed significant tolerance to organic solvents, retaining 48.4% and 28.7% residual activity in 10% v/v acetonitrile and acetone, respectively. Moreover, its storage stability was confirmed, with 68.5% residual activity preserved after 30 days at 4 °C. Remarkably, the immobilized BaCEm retained 58.1% of its activity after 10 reuse cycles, underscoring the potential of polyethyleneimine-impregnated mesoporous silica SBA-15 as an effective support for enzyme immobilization, promising for industrial applications.

Interaction of Micro- and Nanoplastics with Enzymes: The Case of Carbonic Anhydrase.

Microplastics (MPs) and nanoplastics (NPs) have emerged as significant environmental pollutants with potential detrimental effects on ecosystems and human health. Several studies indicate their interaction with enzymes; this topic represents a multifaceted research field encompassing several areas of interest from the toxicological and ecotoxicological impact of MPs and NPs on humans and wildlife to the biodegradation of plastics by microbial enzymes. This review aims to provide a critical analysis of the state-of-the-art knowledge of the interaction of MPs and NPs on the enzyme carbonic anhydrase (CA), providing recent insights, analyzing the knowledge gaps in the field, and drawing future perspectives of the research and its application. CA is a widespread and crucial enzyme in various organisms; it is critical for various physiological processes in animals, plants, and bacteria. It catalyzes the reversible hydration of CO2, which is essential for respiration, acid-base balance, pH homeostasis, ion transport, calcification, and photosynthesis. Studies demonstrate that MPs and NPs can inhibit CA activity with mechanisms including adsorption to the enzyme surface and subsequent conformational changes. In vitro and in silico studies highlight the role of electrostatic and hydrophobic interactions in these processes. In vivo studies present mixed results, which are influenced by factors like particle type, size, concentration, and organism type. Moreover, the potentiality of the esterase activity of CA for plastic degradation is discussed. The complexity of the interaction between CA and MPs/NPs underscores the need for further research to fully understand the ecological and health impacts of MPs and NPs on CA activity and expression and glimpses of the potentiality and perspectives in this field.

Innovative Biosensor Technologies in the Diagnosis of Urinary Tract Infections: A Comprehensive Literature Review.

Urinary tract infections (UTIs) are prevalent bacterial infections globally, posing significant challenges due to their frequency, recurrence, and antibiotic resistance. This review delves into the advancements in UTI diagnostics over the past decade, particularly focusing on the development of biosensor technologies. The emergence of biosensors, including microfluidic, optical, electrochemical, immunosensors, and nanotechnology-based sensors, offers enhanced diagnostic accuracy, reduced healthcare costs. Despite these advancements, challenges such as technical limitations, the need for cross-population validation, and economic barriers for widespread implementation persist. The integration of artificial intelligence and smart devices in UTI diagnostics, highlighting the innovative approaches and their implications for patient care. The article envisions a future where multidisciplinary research and innovation overcome current obstacles, fully leveraging the potential of biosensor technologies to transform biosensor-based UTIs diagnosis. The ultimate goal is to achieve rapid, accurate, and non-invasive diagnostics, making healthcare more accessible and effective.

Structural Analysis of Mammalian Sialic Acid Esterase.

Sialic acid esterase (SIAE) catalyzes the removal of O-acetyl groups from sialic acids found on cell surface glycoproteins to regulate cellular processes such as B cell receptor signalling and apoptosis. Loss-of-function mutations in SIAE are associated with several common autoimmune diseases including Crohn's, ulcerative colitis, and arthritis. To gain a better understanding of the function and regulation of this protein, we determined crystal structures of SIAE from three mammalian homologs, including an acetate bound structure. The structures reveal that the catalytic domain adopts the fold of the SGNH hydrolase superfamily. The active site is composed of a catalytic dyad, as opposed to the previously reported catalytic triad. Attempts to determine a substrate-bound structure yielded only the hydrolyzed product acetate in the active site. Rigid docking of complete substrates followed by molecular dynamics simulations revealed that the active site does not form specific interactions with substrates, rather it appears to be broadly specific to accept sialoglycans with diverse modifications. Based on the acetate bound structure, a catalytic mechanism is proposed. Structural mapping of disease mutations reveals that most are located on the surface of the enzyme and would only cause minor disruptions to the protein fold, suggesting that these mutations likely affect binding to other factors. These results improve our understanding of SIAE biology and may aid in the development of therapies for autoimmune diseases and cancer.

Esterase responsive release of anti-cancer agents from conjugated lipid nanocarrier and the regulatory considerations.

The release of active agents in tumors rather than normal tissues, limits systemic exposure and toxicities. Targeting over-expressed esterase enzyme in the tumor microenvironment can selectively release immune-active agents like Programmed Death-1 (PD-1) and PD-1 ligand inhibitors from ester-sensitive lipid nanocarriers, offering a novel approach compared with conventional therapies. PD-1 and PD-L1 association cause T-cell inactivation, whereas blocking their association improves their cytotoxic mechanism. The patent application US2022/0080051-A1 discloses a novel immune-active agent conjugated with lipid to form a nanocarrier for esterase-sensitive release. These nanocarriers selectively enter leaky vasculature of tumors through enhanced permeability and retention effect, undergo ester cleavage to release agents, and are reported to increase bioavailability by 24 times. Further, with other agents or alone it achieves targeted synergistic cancer therapy. Also, the current patent spotlight delves into the crucial formulation considerations necessary for obtaining successful approval of lipidic nano products from relevant regulatory authorities.

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Clinical profile and management of pediatric hereditary angioedema in resource-constrained settings: our experience from a single centre in North India.

Hereditary angioedema (HAE) is a rare genetic disorder. The pattern of HAE is different in children as compared to adults. There is limited literature from developing countries where all first-line treatments are either unavailable or not easily accessible. Data of children with HAE were retrieved from medical records of patients registered in the Pediatric Immunodeficiency Clinic at our institute. Of the 206 patients with HAE, 61 were diagnosed before the age of 18 years. Male: female ratio was 1.1:1. Median age at onset of symptoms and diagnosis were 6.2 years (range 1-17 years) and 10.7 years (range 1.5-18 years) respectively. Median delay in diagnosis was 4.9 years (range 0-16 years). The commonest presentation was facial swelling (51/61) followed by swelling of extremities (47/61). Laryngeal edema and abdominal symptoms were reported in 28/61 and 31/61 patients respectively. Abdominal attacks were found to be less common in children as compared to adults. Most patients in our cohort received fresh-frozen plasma (n = 5/61) as on-demand therapy. Long-term prophylaxis included attenuated androgens (n = 25/61) and tranexamic acid (n = 23/61). Median duration of follow-up was 2242 patient months. One patient died on follow-up in this cohort. This is the largest single-centre cohort of pediatric HAE from resource-constrained settings. Facial attacks were more common, and there were significant delays in diagnosis when the age of onset of symptoms was younger. Gastrointestinal symptoms were less common in children than adults. HIGHLIGHTS: One of the largest single-centre cohorts of pediatric HAE and the only one from resource-constrained settings. There were significant delays in diagnosis when the age of onset of symptoms was younger. Abdominal attacks were found to be less common in children as compared to adults.

Study on the Inhibitory Effect of Bioactive Peptides Derived from Yak Milk Cheese on Cholesterol Esterase.

The bioactive peptides derived from yak milk cheese exhibited cholesterol-lowering properties. However, there was limited research on their inhibitory effects on cholesterol esterase (CE) and elucidation of their potential inhibitory mechanisms. In this study, we identified CE-inhibiting peptides through virtual screening and in vitro assays. Additionally, molecular docking and molecular dynamics studies were conducted to explore the mechanisms. The results indicated that peptides RK7 (RPKHPIK), KQ7 (KVLPVPQ), QP13 (QEPVLGPVRGPFP), TL9 (TPVVVPPFL), VN10 (VYPFPGPIPN), LQ10 (LPPTVMFPPQ), and SN12 (SLVYPFPGPIPN) possessed molecular weights of less than 1.5 kDa and a high proportion of hydrophobic amino acids, demonstrating notable inhibitory effects on CE. Molecular docking and dynamics revealed that peptides RK7, KQ7, QP13, and VN10 bound to key amino acid residues Arg423, His435, and Ser422 of CE through hydrogen bonds, hydrophobic interactions, salt bridges, and π-π stacking, occupying the substrate-binding site and exerting inhibitory effects on CE. The four peptides were further synthesized to verify their CE-inhibitory effects in vitro. RK7, KQ7, QP13, and VN10 exhibited inhibitory activity on CE with IC50 values of 8.16 × 10-7 mol/L, 8.10 × 10-7 mol/L, 4.63 × 10-7 mol/L, and 7.97 × 10-7 mol/L; RK7, KQ7, QP13, and VN10 were effective in inhibiting CE after simulated gastrointestinal digestion, especially with a significant increase in the inhibitory activity of KQ7 and RK7, respectively. Our findings suggested that bioactive peptides from yak milk cheese represented a novel class of potential CE inhibitors.

In-silico characterization of a hypothetical protein of Sulfobacillus sp. hq2 for degradation of phthalate diesters.

Phthalate plasticizers are hazardous compounds capable of causing endocrine disruption, cancers, and developmental disorders. Phthalate diesters are commonly used plasticizers in plastic products (PVC pipes) that leach out into the environment due to changes in temperature, pressure, and pH, posing harmful effects on different life forms. Bioremediation of phthalate diesters utilizing bacterial esterase has been recognized as an efficient approach but few effective esterases capable of degrading a wide range of phthalate diesters have been identified. Further, the thermostability of these esterases is a highly desirable property for their applications in diverse in-situ conditions. In this present in-silico study a hypothetical protein (POB10642.1) as a high-potential esterase from a thermostable strain of Sulfobacillus sp. hq2 has been characterized. Analysis revealed a significant sequence identity of 42.67 % and structural similarity (RMSD 0.557) with known phthalate diester degrading EstS1 esterase and a high Tm range of 55-66 °C. Structural analysis revealed the presence of two cavities on the surface mediating toward the catalytic site forming a catalytic tunnel. The enzyme POB10642.1 has significant molecular docking binding energies in the range of -5.4 to -7.5 kcal/mol with several phthalate diesters, including Diethyl phthalate, Dipropyl phthalate, Dibutyl phthalate, Dipentyl phthalate, Dihexyl phthalate, Benzyl butyl phthalate, Dicyclohexyl phthalate, and Bis(2-ethylhexyl) phthalate. High stability of binding during 100 ns molecular dynamics simulations revealed efficient and stable binding of the enzyme with a wide range of phthalate diesters at its active site, demonstrating the ability of the identified esterase to interact with and degrade diverse phthalate diesters. Therefore, POB10642.1 esterase can be an efficient candidate to be utilized in the development of enzyme-based bioremediation technologies to reduce the toxic levels of phthalate diesters.

Sequence analysis, homology modeling, tissue expression, and potential functions of seven putative acetylcholinesterases in the spider Cupiennius salei.

Acetylcholine esterases (AChEs) are essential enzymes in cholinergic synapses, terminating neurotransmission by hydrolysing acetylcholine. While membrane bound AChEs at synaptic clefts efficiently perform this task, soluble AChEs are less stable and effective, but function over broader areas. In vertebrates, a single gene produces alternatively spliced forms of AChE, whereas invertebrates often have multiple genes, producing both enzyme types. Despite their significance as pesticide targets, the physiological roles of invertebrate AChEs remain unclear. Here, we characterized seven putative AChEs in the wandering spider, Cupiennius salei, a model species for neurophysiological studies. Sequence analyses and homology modeling predicted CsAChE7 as the sole stable, membrane-bound enzyme functioning at synaptic clefts, while the others are likely soluble enzymes. In situ hybridization of sections from the spider's nervous system revealed CsAChE7 transcripts co-localizing with choline acetyltransferase in cells that also exhibited AChE activity. CsAChE7 transcripts were also found in rapidly adapting mechanosensory neurons, suggesting a role in precise and transient activation of postsynaptic cells, contrasting with slowly adapting, also cholinergic, neurons expressing only soluble AChEs, which allow prolonged activation of postsynaptic cells. These findings suggest that cholinergic transmission is influenced not only by postsynaptic receptors but also by the enzymatic properties regulating acetylcholine clearance. We also show that acetylcholine is a crucial neurotransmitter in the spider's visual system and sensory and motor pathways, but absent in excitatory motor neurons at neuromuscular junctions, consistent with other arthropods. Our findings on sequence structures may have implications for the development of neurological drugs and pesticides.

A cub and sushi domain-containing protein with esterase-like activity confers insecticide resistance in the Indian malaria vector Anopheles stephensi.

Chemical insecticides (organophosphates and pyrethroids) in the form of IRS (Indoor Residual Sprays) and LLINs (Long Lasting Insecticidal Nets) are the cornerstone for vector control, globally. However, their incessant use has resulted in widespread development of resistance in mosquito vectors, warranting continuous monitoring and investigation of the underlying mechanisms of resistance. Here, we identified a previously uncharacterized- Cub and Sushi Domain containing Insecticide Resistance (CSDIR) protein and generated evidence for its role in mediating insecticide resistance in the Anopheles stephensi. A strong binding affinity of the CSDIR protein towards different classes of insecticide molecules-malathion (KD 6.43 µM) and deltamethrin (KD 46.7 µM) were demonstrated using MD simulation studies and Surface Plasmon Resonance (SPR) experiments. Further, the recombinant CSDIR913-1190 protein exhibited potent esterase-like activity (α-naphthyl acetate (α-NA)- 1.356 ± 0.262 mM/min/mg and ß-naphthyl acetate (ß -NA)- 1.777 ± 0.220 mM/min/mg). Interestingly, dsRNA-mediated gene silencing of the CSDIR transcripts caused >60% mortality in resistant An. stephensi upon 1-h exposure to deltamethrin and malathion insecticides, compared to the control group. A significant reduction in the esterase-like activity was also observed against α-NA (p = 0.004) and ß-NA (p = 0.025) in CSDIR silenced mosquitoes compared to the control group. Using computational analysis and experimental data, our results provided significant evidence of the involvement of the CSDIR protein in mediating insecticide resistance in Anopheles mosquitoes. Thereby making the CSDIR protein, a novel candidate for exploration of novel insecticide molecules. These data would also be helpful in further understanding the development of metabolic resistance by the Anopheles vector.

Understanding pyrethrin biosynthesis: toward and beyond natural pesticide overproduction.

Pyrethrins are natural insecticides biosynthesised by Asteraceae plants, such as Tanacetum cinerariifolium and have a long history, dating back to ancient times. Pyrethrins are often used as low-persistence and safe insecticides to control household, horticultural, and agricultural insect pests. Despite its long history of use, pyrethrin biosynthesis remains a mystery, presenting a significant opportunity to improve yields and meet the growing demand for organic agriculture. To achieve this, both genetic modification and non-genetic methods, such as chemical activation and priming, are indispensable. Plants use pyrethrins as a defence against herbivores, but pyrethrin biosynthesis pathways are shared with plant hormones and signal molecules. Hence, the insight that pyrethrins may play broader roles than those traditionally expected is invaluable to advance the basic and applied sciences of pyrethrins.

Structural, Biochemical, and Phylogenetic Analysis of Bacterial and Fungal Carbohydrate Esterase Family 15 Glucuronoyl Esterases in the Rumen.

Glucuronoyl esterases (GEs) are carbohydrate active enzymes in carbohydrate esterase family 15 which are involved in the hydrolysis of lignin-carbohydrate complexes. They are encoded by a wide range of aerobic and anaerobic fungi and bacteria inhabiting diverse environments. The rumen microbiome is a complex microbial community with a wide array of enzymes that specialize in deconstructing plant cell wall carbohydrates. Enzymes from the rumen tend to show low similarity to homologues found in other environments, making the rumen microbiome a promising source for the discovery of novel enzymes. Using a combination of phylogenetic and structural analysis, we investigated the structure-function relationship of GEs from the rumen bacteria Fibrobacter succinogenes and Ruminococcus flavefaciens, and from the rumen fungus, Piromyces rhizinflata. All adopt a canonical α/ß hydrolase fold and possess a structurally conserved Ser-His-Glu/Asp catalytic triad. Structural variations in the enzymes are localized to loops surrounding the active site. Analysis of the active site structures in these enzymes emphasized the importance of structural plasticity in GEs with non-canonical active site conformations. We hypothesize that interkingdom HGT events may have contributed to the diversity of GEs in the rumen, and this is demonstrated by the phylogenetic and structural similarity observed between rumen bacterial and fungal GEs. This study advances our understanding of the structure-function relationship in glucuronoyl esterases and illuminates the evolutionary dynamics that contribute to enzyme diversity in the rumen microbiome.

Acute Abdominal Pain as the Initial Presentation of an Acquired C1 Inhibitor Deficiency.

Introduction: Acquired angioedema (AAE), a rare cause of adult-onset non-urticarial mucocutaneous angioedema, can present as acute abdomen, a frequent complaint in the emergency room (ER), often leading to unnecessary and potentially harmful procedures. Case Presentation: We report a 47-year-old hypertense male, controlled with an angiotensin converting enzyme inhibitor (ACEI), who presented in the ER with progressively worsening abdominal pain, nausea, and vomiting, and a radiologic workup revealing small intestine thickening, initially diagnosed with ACEI-induced angioedema. However, further investigation revealed low serum levels of C4, C1q, and C1 inhibitors, with an abnormal function of the latter, favoring the diagnosis of AAE instead. The frequent association of this condition with lymphoproliferative disorders encouraged further studies, which unveiled a monoclonal gammopathy IgM/Kappa, representing an increased risk of Waldenström macroglobulinemia, non-Hodgkin lymphoma, and multiple myeloma. Discussion: AAE should be regarded as an important differential diagnosis in patients presenting with acute abdomen in the ER, especially when more common causes are excluded. A correct and early diagnosis may represent a chance for a better prognosis of underlying diseases.

Introdução: O angioedema adquirido (AA), causa rara de angioedema mucocutâneo não urticariforme de início tardio, pode ter como apresentação inicial abdómen agudo, motivo frequente de admissão no serviço de urgência (SU), promovendo frequentemente procedimentos desnecessários e potencialmente prejudiciais. Apresentação do caso: Um homem de 47 anos, hipertenso e controlado com um inibidor da enzima conversora de angiotensina (IECA), recorreu ao SU por um quadro de dor abdominal com agravamento progressivo, náuseas e vómitos. A investigação radiológica inicial revelou espessamento do intestino delgado, culminando num diagnóstico preliminar de angioedema induzido por IECA. No entanto, uma investigação mais aprofundada em regime ambulatório revelou níveis séricos reduzidos de C4, C1q e de inibidor de C1, com função anormal deste último, favorecendo o diagnóstico de AA. A associação frequente desta condição com distúrbios linfoproliferativos incentivou investigação adicional, que revelou uma gamopatia monoclonal IgM/Kappa, representando um risco aumentado de macroglobulinemia de Waldenström, linfoma não-Hodgkin e mieloma múltiplo. Discussão: O AA deve ser considerado um diagnóstico diferencial de abdómen agudo, principalmente após exclusão de causas mais frequentes. Um diagnóstico precoce pode contribuir para um melhor prognóstico da patologia subjacente.

Morin attenuated the global cerebral ischemia via antioxidant, anti-inflammatory, and antiapoptotic mechanisms in rats.

Global cerebral ischemia is one of the major causes of memory and cognitive impairment. Hyperactivation of acetylcholine esterase (AChE), oxidative stress, and inflammation are reported to cause memory and cognitive impairment in global cerebral ischemia. Morin, a flavonoid, is reported to have neuroprotective properties through its antioxidant and anti-inflammatory in multiple neurological diseases. However, its neuroprotective effects and memory and cognition enhancement have not yet been investigated. In the present study, we have determined the memory and cognition, and neuroprotective activity of Morin in bilateral common carotid artery occlusion and reperfusion (BCCAO/R) in Wistar rats. We found that Morin treatment significantly improved motor performance like grip strength and rotarod. Further, Morin improved memory and cognition in BCCAO rats by decreasing the AchE enzyme activity and enhancing the acetylcholine (Ach) levels. Additionally, Morin exhibited neuroprotection by ameliorating oxidative stress, neuroinflammation, and apoptosis in BCCAO rats. These findings confirm that Morin could enhance memory and cognition by ameliorating AchE activity, oxidative stress, neuroinflammation, and apoptosis in global cerebral ischemia. Therefore, Morin could be a promising neuroprotective and memory enhancer against global cerebral ischemic injury.

Pectin Remodeling and Involvement of AtPME3 in the Parasitic Plant-Plant Interaction, Phelipanche ramosa-Arabidospis thaliana.

Phelipanche ramosa is a root parasitic plant fully dependent on host plants for nutrition and development. Upon germination, the parasitic seedling develops inside the infected roots a specific organ, the haustorium, thanks to the cell wall-degrading enzymes of haustorial intrusive cells, and induces modifications in the host's cell walls. The model plant Arabidopsis thaliana is susceptible to P. ramosa; thus, mutants in cell wall metabolism, particularly those involved in pectin remodeling, like Atpme3-1, are of interest in studying the involvement of cell wall-degrading enzymes in the establishment of plant-plant interactions. Host-parasite co-cultures in mini-rhizotron systems revealed that parasite attachments are twice as numerous and tubercle growth is quicker on Atpme3-1 roots than on WT roots. Compared to WT, the increased susceptibility in AtPME3-1 is associated with reduced PME activity in the roots and a lower degree of pectin methylesterification at the host-parasite interface, as detected immunohistochemically in infected roots. In addition, both WT and Atpme3-1 roots responded to infestation by modulating the expression of PAE- and PME-encoding genes, as well as related global enzyme activities in the roots before and after parasite attachment. However, these modulations differed between WT and Atpme3-1, which may contribute to different pectin remodeling in the roots and contrasting susceptibility to P. ramosa. With this integrative study, we aim to define a model of cell wall response to this specific biotic stress and indicate, for the first time, the role of PME3 in this parasitic plant-plant interaction.