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Bacteria produce a remarkably diverse range of glycoside hydrolases to metabolize glycans from the environment as a primary source of nutrients, and to promote the colonization and infection of a host. Here we focus on EndoE, a multi-modular glycoside hydrolase secreted by Enterococcus faecalis , one of the leading causes of healthcare-associated infections. We provide X-ray crystal structures of EndoE, which show an architecture composed of four domains, including GH18 and GH20 glycoside hydrolases connected by two consecutive three α-helical bundles. We determine that the GH20 domain is an exo-β-1,2- N -acetylglucosaminidase, whereas the GH18 domain is an endo-β-1,4- N -acetylglucosaminidase that exclusively processes the central core of complex-type or high-mannose-type N -glycans. Both glycoside hydrolase domains act in a concerted manner to process diverse N -glycans on glycoproteins, including therapeutic IgG antibodies. EndoE combines two enzyme domains with distinct functions and glycan specificities to play a dual role in glycan metabolism and immune evasion. EndoE is a multi-domain glycoside hydrolase of the human pathogen Enterococcus faecalis . Here, the authors present crystal structures of EndoE and provide biochemical insights into the molecular basis of EndoE’s substrate specificity and catalytic mechanism.

Bacteroidales (syn. Bacteroidetes) are prominent members of the human gastrointestinal ecosystem mainly due to their efficient glycan-degrading machinery, organized into gene clusters known as polysaccharide utilization loci (PULs). A single PUL was reported for catabolism of high-mannose (HM) N -glycan glyco-polypeptides in the gut symbiont Bacteroides thetaiotaomicron , encoding a surface endo-β-N-acetylglucosaminidase (ENGase), BT3987. Here, we discover an ENGase from the GH18 family in B. thetaiotaomicron , BT1285, encoded in a distinct PUL with its own repertoire of proteins for catabolism of the same HM N -glycan substrate as that of BT3987. We employ X-ray crystallography, electron microscopy, mass spectrometry-based activity measurements, alanine scanning mutagenesis and a broad range of biophysical methods to comprehensively define the molecular mechanism by which BT1285 recognizes and hydrolyzes HM N -glycans, revealing that the stabilities and activities of BT1285 and BT3987 were optimal in markedly different conditions. BT1285 exhibits significantly higher affinity and faster hydrolysis of poorly accessible HM N -glycans than does BT3987. We also find that two HM-processing endoglycosidases from the human gut-resident Alistipes finegoldii display condition-specific functional properties. Altogether, our data suggest that human gut microbes employ evolutionary strategies to express distinct ENGases in order to optimally metabolize the same N- glycan substrate in the gastroinstestinal tract. The human gut microbiome has a substantial impact on human health. Here, the authors find that prominent human gut microbes express functionally distinct surface endo-β-N-acetylglucosaminidases encoded by different polysaccharide utilization loci to optimally metabolize the same oligomannose N- glycan substrate in the gastrointestinal tract.

Bacterial pathogens have evolved intricate mechanisms to evade the human immune system, including the production of immunomodulatory enzymes. Streptococcus pyogenes serotypes secrete two multi-modular endo-β- N -acetylglucosaminidases, EndoS and EndoS2, that specifically deglycosylate the conserved N -glycan at Asn297 on IgG Fc, disabling antibody-mediated effector functions. Amongst thousands of known carbohydrate-active enzymes, EndoS and EndoS2 represent just a handful of enzymes that are specific to the protein portion of the glycoprotein substrate, not just the glycan component. Here, we present the cryoEM structure of EndoS in complex with the IgG1 Fc fragment. In combination with small-angle X-ray scattering, alanine scanning mutagenesis, hydrolytic activity measurements, enzyme kinetics, nuclear magnetic resonance and molecular dynamics analyses, we establish the mechanisms of recognition and specific deglycosylation of IgG antibodies by EndoS and EndoS2. Our results provide a rational basis from which to engineer novel enzymes with antibody and glycan selectivity for clinical and biotechnological applications. Bacterial pathogens have evolved intricate mechanisms to evade the human immune system, including the production of immunomodulatory enzymes. Here, the authors establish the mechanisms of recognition and specific deglycosylation of IgG antibodies by the multi-modular enzymes EndoS and EndoS2

Determining optimum inventory replenishment decisions are critical for retail businesses with uncertain demand. The problem becomes particularly challenging when multiple products with different lead times and cross-product constraints are considered. This paper addresses the aforementioned challenges in multi-product, multi-period inventory management using deep reinforcement learning (deep RL). The proposed approach improves upon existing methods for inventory control on three fronts: (1) concurrent inventory management of a large number (hundreds) of products under realistic constraints, (2) minimal retraining requirements on the RL agent under system changes through the definition of an individual product meta-model, (3) efficient handling of multi-period constraints that stem from different lead times of different products. We approach the inventory problem as a special class of dynamical system control, and explain why the generic problem cannot be satisfactorily solved using classical optimisation techniques. Subsequently, we formulate the problem in a general framework that can be used for parallelised decision-making using off-the-shelf RL algorithms. We also benchmark the formulation against the theoretical optimum achieved by linear programming under the assumptions that the demands are deterministic and known apriori. Experiments on scales between 100 and 220 products show that the proposed RL-based approaches perform better than the baseline heuristics, and quite close to the theoretical optimum. Furthermore, they are also able to transfer learning without retraining to inventory control problems involving different number of products.

Corynebacterium diphtheriae clade species secrete single-domain endo-β- N -acetylglucosaminidases (ENGases) that specifically bind to human IgG antibodies and hydrolyze their N297-linked glycans. Here, we define the molecular mechanisms of IgG-specific deglycosylation for the entire family of corynebacterial IgG-specific ENGases, including but not limited to CU43 and CM49. By solving the crystal structure of CU43 in a 1:1 complex with the IgG1 Fc region, combined with targeted and saturation mutagenesis analysis and activity measurements using engineered antibodies, we establish an inter-protomeric mechanism of recognition and deglycosylation of IgG antibodies. Using in silico modeling, small-angle X-ray scattering and saturation mutagenesis we determine that CM49 uses a unique binding site on the Fc region, to process N297-linked glycans. Moreover, we demonstrate that CU43 treatment is highly effective in abrogating Fc effector functions in humanized mouse models, while preserving the neutralizing capacity of anti-influenza IgG antibodies, thereby conferring protection against lethal influenza challenge. Here the authors define an inter-protomeric mechanism of deglycosylation of human IgG antibodies for corynebacterial IgG-specific ENGases and demonstrate that in vivo CU43 treatment preserve the neutralizing capacity of anti-influenza IgG antibodies.

In folklore medicine, Vitex negundo leaf is used to treat inflammation, pain, runny nose, itching, tumor etc. Different fractions of crude methanol extract of leaf of Vitex negundo Linn. were tested to evaluate antioxidant, analgesic, thrombolytic, and antibacterial activities. Crude methanol (MeOH) extract and its fractions i.e. petroleum ether (PEFS), CHCl3 (CFS), CCl4 (CTFS), aqueous (AQFS) were subjected to antioxidant activity by DPPH free radical scavenging assay. Analgesic activity was investigated by acetic acid induced writhing method at the dose of 250 and 500mg/kg body weight. Furthermore, thrombolytic activity was evaluated by clot lysis method and antibacterial activity by disk diffusion assay. In DPPH radical scavenging assay, crude extract presented the highest (IC50 value 25µg/ml) radical scavenging activity. Different fractions of extract at the tested doses showed significant (P<0.05) analgesic activity that was comparable to standard diclofenac sodium (80.32 % at 25mg/kg). Also different fractions revealed different range of antibacterial activity against different species of bacteria at different doses. Different fractions of V. negundo leaf disclosed potent antioxidant, thrombolytic, analgesic and antibacterial activities that support the ethnomedical uses of the plant.

Traditional linear discriminant analysis (LDA) approach discards the eigenvalues which are very small or equivalent to zero, but quite often eigenvectors corresponding to zero eigenvalues are the important dimensions for discriminant analysis. We propose an objective function which would utilize both the principal as well as nullspace eigenvalues and simultaneously inherit the class separability information onto its latent space representation. The idea is to build a convolutional neural network (CNN) and perform the regularized discriminant analysis on top of this and train it in an end-to-end fashion. The backpropagation is performed with a suitable optimizer to update the parameters so that the whole CNN approach minimizes the within class variance and maximizes the total class variance information suitable for both multi-class and binary class classification problems. Experimental results on four databases for multiple computer vision classification tasks show the efficacy of our proposed approach as compared to other popular methods.

Objective: The purpose of this study was to characterize the circulating Peste des Petits Ruminants virus (PPRV) from slaughtered goats and conduct a phylogenetic analysis of the N gene of PPRV. Materials and Methods: A total of 196 slaughtered goats were investigated at the marketplaces of Mymensingh division from January 2019 to March 2021. Lungs, spleen, and mesenteric lymph nodes were collected for histology and molecular study. In-house developed Reverse- Transcriptase-Polymerase Chain Reaction (RT-PCR) protocols were carried out using designed primer sets (PPRV NF-gctctgtgattgcggctgagc and PPRV NR-cctggtcctccagaatcttggcc). The CLC sequence viewer was used for phylogenetic analysis. Results: Grossly pneumonic lungs, shrinkage spleen, and enlarged mesenteric lymph nodes with hemorrhages were recorded. Both intracytoplasmic and intranuclear inclusion bodies were seen in lymphocytes of the mesenteric lymph node, spleen, and lungs. PPRV was detected in 37 goats (18.9%) by RT-PCR test. The 402-bp amplicon was generated in PPRV-positive cases. The phylo¬genetic analysis showed that the studied PPRV isolates of the Mymensingh division belonged to lineage IV. Conclusion: The prevalence of PPR was 18.9% in slaughtered goats at marketplaces in the Mymensingh division. Slaughterhouses may be a source of PPRV, and it can be horizontally trans¬mitted from the meat market to the farm. Restricting sick animal movement within the country, mass PPR vaccination campaigns, increased awareness, and improved biosecurity in the meat market may lessen the incidence of PPR in goats.

Sustainable bitter gourd production requires optimising the combined organic and inorganic nutrient management. Hence, a field experiment was conducted to evaluate the impact of combined organic and inorganic nutrient amendments on bitter gourd productivity, quality, nutrient use efficiency, soil microbial activity, soil health, and profitability. Treatments were T : control, T : recommended dose of inorganic N-P-K-S-Zn-B at 120-40-85-20-3-2 kg · ha , T : 5 t · ha vermicompost (VC) + 50% of NPKSZnB, T : 2.5 t · ha poultry manure (PM) + 50% of NPKSZnB, T : 5 t · ha VC + 75% of NPKSZnB, T : 2.5 t · ha PM + 75% of NPKSZnB, T : 5 t · ha cow dung (CD) + 75% of NPKSZnB, T : 5 t · ha VC + 5 t · ha CD + 50% of NPKSZnB, and T : 5 t · ha VC + 5 t · ha CD + 25% of NPKSZnB. Integrating 5 t · ha VC + 5 t · ha CD with 50% of NPKSZnB fertiliser (T ) significantly boosted the bitter gourd fresh fruit yield (13.1 t · ha ), a 192% higher over control, with larger fruits, higher fruit count, and greater vine length. Treatment T also excelled in vitamin C (77.6 mg · 100 g ), β-carotene (122 mcg · 100 g ), protein (18.1%), moisture content (93.4%), and total soluble solids (4.0°Brix), alongside enhanced nutrient uptake, soil health, robust microbial populations, and economic returns (4552 US$ · ha ). Treatment T exhibited the highest agronomic and removal efficiencies for key nutrients. Therefore, combined application of 5 t · ha VC + 5 t · ha CD with 50% of NPKSZnB fertiliser offer a promising approach for sustainable bitter gourd production. This method not only boosts yield and quality but also improves soil health and minimises environmental risks through reducing chemical fertiliser use.

Objective: Peste des petits ruminants (PPR) virus is the main infectious cause of goat mortality in Bangladesh, and co-infection may make diseases more severe. This study aimed to detect PPR and co-infecting diseases in goats. Materials and Methods: One hundred goats suspected to be infected with the PPR virus were collected from various areas of Mymensingh district, Bangladesh. A systemic post-mortem examination was carried out on PPR-suspected goats. Lungs, spleen, and lymph nodes (pre-scapular) were used for ribonucleic acid extraction, whereas lungs and mesenteric lymph nodes were used for deoxyribonucleic acid extraction. Seven-pair primer sets were used for molecular detection of pathogens specific for PPR, goat pox, contagious ecthyma (Orf), foot and mouth disease (FMD) virus, Klebsiella sp., and Mycobacterium sp. Reverse transcriptase-polymerase chain reaction (RT-PCR) or polymerase chain reaction (PCR) were used to find the exact cause. Results: Out of 100 PPR-suspected goats examined, 55 goats were confirmed as PPR-detected by RT-PCR. Among the 55 PPR-positive goats, 2 were co-infected with goat pox, 2 with tuberculosis, 10 with Klebsiella sp. infection, and 6 with FMD as detected by PCR and RT-PCR. Moreover, 12 goats were co-infected with PPRV and fascioliasis. Conclusion: About 58% of PPR virus-infected goats were co-infected with other organisms. There is a need to design technology to detect the state of co-infectivity at its early onset and future preventive and therapeutic strategies for co-infecting diseases. This is the first study in Bangladesh to describe co-infecting diseases of goats along with PPR.