Catalytic action of alternansucrase on sucrose under in vitro simulated gastric conditions.

Alternansucrase, a glucosyltransferase, is currently used to produce slowly digestible alternan oligosaccharides or maltooligosaccharides from sucrose. These oligosaccharides are popular for food fortification to lower postprandial glucose levels. This study aimed to explore the enzymatic reaction of alternansucrase in simulated in vitro gastric reaction conditions. Under the studied conditions, SucroSEB (a model enzyme for alternansucrase) hydrolyzed the sucrose and transglycosylated the glucose to produce glucans, both in the absence and presence of acceptors. The preference of the acceptor was maltose˃ raffinose˃ lactose. The rate of sucrose hydrolysis was significantly higher in the presence of maltose (p = 0.024). The glucans formed during the reaction included oligomers (DP 3-10) and polymers (DP ≥ 11), both of which increased over time. These glucans contained α-1,3 and α-1,6 glycosidic linkages, confirmed by 1H and 13C NMR. They were slowly and partially digestible in the presence of rat intestinal extract in contrast to the complete and rapid digestion of starch. The glucans formed after a longer gastric reaction time exhibited higher dietary fiber potential (19.145 ± 4.77 %; 60 min) compared to those formed during the initial phase (2.765 ± 0.19 %; 15 min). Overall, this study demonstrated the efficacy of SucroSEB in converting sucrose to slowly and partially digestible glucans under simulated in vitro gastric conditions.

Wild Patagonian yeast improve the evolutionary potential of novel interspecific hybrid strains for lager brewing.

Lager yeasts are limited to a few strains worldwide, imposing restrictions on flavour and aroma diversity and hindering our understanding of the complex evolutionary mechanisms during yeast domestication. The recent finding of diverse S. eubayanus lineages from Patagonia offers potential for generating new lager yeasts with different flavour profiles. Here, we leverage the natural genetic diversity of S. eubayanus and expand the lager yeast repertoire by including three distinct Patagonian S. eubayanus lineages. We used experimental evolution and selection on desirable traits to enhance the fermentation profiles of novel S. cerevisiae x S. eubayanus hybrids. Our analyses reveal an intricate interplay of pre-existing diversity, selection on species-specific mitochondria, de-novo mutations, and gene copy variations in sugar metabolism genes, resulting in high ethanol production and unique aroma profiles. Hybrids with S. eubayanus mitochondria exhibited greater evolutionary potential and superior fitness post-evolution, analogous to commercial lager hybrids. Using genome-wide screens of the parental subgenomes, we identified genetic changes in IRA2, IMA1, and MALX genes that influence maltose metabolism, and increase glycolytic flux and sugar consumption in the evolved hybrids. Functional validation and transcriptome analyses confirmed increased maltose-related gene expression, influencing greater maltotriose consumption in evolved hybrids. This study demonstrates the potential for generating industrially viable lager yeast hybrids from wild Patagonian strains. Our hybridization, evolution, and mitochondrial selection approach produced hybrids with high fermentation capacity and expands lager beer brewing options.

Efficacy of ferric carboxymaltose on haemoglobin response among older patients with gastrointestinal bleeding: a randomised clinical trial.

BACKGROUND: Acute gastrointestinal bleeding (AGIB) is common in older patients but the use of iron in this context remains understudied. AIMS: This study aimed to evaluate prospectively the efficacy of ferric carboxymaltose to treat anaemia in older patients after AGIB. METHODS: This randomised double-blinded placebo-controlled clinical trial was conducted in 10 French centres. Eligible patients were 65 years or more, had controlled upper or lower gastrointestinal bleeding and a haemoglobin level of 9-11 g/dl. Patients were randomly assigned, in a 1:1 ratio, to receive either one intravenous iron injection of ferric carboxymaltose or one injection of saline solution. The primary endpoint was the difference in haemoglobin level between day 0 and day 42. Secondary endpoints were treatment-emergent adverse events, serious adverse events, rehospitalisation and improvement of quality of life (QOL) at day 180. RESULTS: From January 2013 to January 2017, 59 patients were included. The median age of patients was 81.9 [75.8, 87.3] years. At day 42, a significant difference in haemoglobin level increase was observed (2.49 g/dl in the ferric carboxymaltose group vs. 1.56 g/dl in the placebo group, P = 0.02). At day 180, QOL, measured on European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30, improved by 10.5 points in the ferric carboxymaltose group and by 8.2 points in the placebo group (P = 0.56). Rates of adverse events and rehospitalisation were similar in the two groups. CONCLUSIONS: Intravenous iron seems safe and effective to treat anaemia in older patients after AGIB and should be considered as a standard-of-care treatment. ClinicalTrials.gov (NCT01690585).

Protecting Lyophilized Escherichia coli Adenylate Kinase.

Drying protein-based drugs, usually via lyophilization, can facilitate storage at ambient temperature and improve accessibility but many proteins cannot withstand drying and must be formulated with protective additives called excipients. However, mechanisms of protection are poorly understood, precluding rational formulation design. To better understand dry proteins and their protection, we examine Escherichia coli adenylate kinase (AdK) lyophilized alone and with the additives trehalose, maltose, bovine serum albumin, cytosolic abundant heat soluble protein D, histidine, and arginine. We apply liquid-observed vapor exchange NMR to interrogate the residue-level structure in the presence and absence of additives. We pair these observations with differential scanning calorimetry data of lyophilized samples and AdK activity assays with and without heating. We show that the amino acids do not preserve the native structure as well as sugars or proteins and that after heating the most stable additives protect activity best.

A meta-analysis of ferric carboxymaltose versus other intravenous iron preparations for the management of iron deficiency anemia during pregnancy.

Objective: We conducted a meta-analysis of randomized clinical trials evaluating the clinical effects of ferric carboxymaltose therapy compared to other intravenous iron in improving hemoglobin and serum ferritin in pregnant women. We also assessed the safety of ferric carboxymaltose vs. other intravenous iron. Data source: EMBASE, PubMed, and Web of Science were searched for trials related to ferric carboxymaltose in pregnant women, published between 2005 and 2021. We also reviewed articles from google scholar. The keywords "ferric carboxymaltose," "FCM," "intravenous," "randomized," "pregnancy," "quality of life," and "neonatal outcomes" were used to search the literature. The search was limited to pregnant women. Selection of studies: Studies related to ferric carboxymaltose in pregnancy were scanned. Observational studies, review articles, and case reports were excluded. Randomized studies in pregnant women involving ferric carboxymaltose and other intravenous iron formulations were shortlisted. Of 256 studies, nine randomized control trials were selected. Data collection: Two reviewers independently extracted data from nine selected trials. Data synthesis: The final effect size for increase in hemoglobin after treatment was significant for ferric carboxymaltose vs. iron sucrose/iron polymaltose (standard mean difference 0.89g/dl [95% confidence interval 0.27,1.51]). The final effect size for the increase in ferritin after treatment was more for ferric carboxymaltose vs. iron sucrose/iron polymaltose (standard mean difference 22.53µg/L [-7.26, 52.33]). No serious adverse events were reported with ferric carboxymaltose or other intravenous iron. Conclusion: Ferric carboxymaltose demonstrated better efficacy than other intravenous iron in increasing hemoglobin and ferritin levels in treating iron deficiency anemia in pregnant women.

Effect of high-dose intravenous iron injection on hepatic function in a rat model of cirrhosis.

OBJECTIVE: To investigate the hepatic effects of high-dose intravenous (IV) iron, including those on liver function and the degree of fibrosis, in a rat model of cirrhosis. METHODS: We evenly allocated 25 Sprague-Dawley rats into five groups: normal rats (control group), cirrhotic rats receiving IV normal saline (liver cirrhosis [LC] group), and cirrhotic rats receiving 20, 40, or 80 mg/kg IV ferric carboxymaltose (LC-iron20, LC-iron40, and LC-iron80 group, respectively). Biochemical parameters were compared at 0, 7, 14, 21, and 28 days. The degrees of hepatic fibrosis and iron deposition were evaluated. Inflammatory and oxidative stress markers were also compared. RESULTS: There were no significant differences in the 28-day serum alanine aminotransferase levels among the LC-iron20, LC-iron40, and LC-iron80 groups (69 ± 7, 1003 ± 127, 1064 ± 309, 919 ± 346, and 820 ± 195 IU/L in the control, LC, LC-iron20, LC-iron40, and LC-iron80 groups, respectively). Hepatic iron accumulation increased in a dose-dependent manner, but the degree of hepatic fibrosis was comparable among the groups. The inflammatory and oxidative stress marker levels did not differ significantly according to the IV iron dose. CONCLUSIONS: Administration of IV iron at various high doses appears safe in our rat model of cirrhosis.

Allosteric modulation of fluorescence revealed by hydrogen bond dynamics in a genetically encoded maltose biosensor.

Genetically encoded fluorescent biosensors (GEFBs) proved to be reliable tracers for many metabolites and cellular processes. In the simplest case, a fluorescent protein (FP) is genetically fused to a sensing protein which undergoes a conformational change upon ligand binding. This drives a rearrangement in the chromophore environment and changes the spectral properties of the FP. Structural determinants of successful biosensors are revealed only in hindsight when the crystal structures of both ligand-bound and ligand-free forms are available. This makes the development of new biosensors for desired analytes a long trial-and-error process. In the current study, we conducted µs-long all atom molecular dynamics (MD) simulations of a maltose biosensor in both the apo (dark) and holo (bright) forms. We performed detailed hydrogen bond occupancy analyses to shed light on the mechanism of ligand induced conformational change in the sensor protein and its allosteric effect on the chromophore environment. We find that two strong indicators for distinguishing bright and dark states of biosensors are due to substantial changes in hydrogen bond dynamics in the system and solvent accessibility of the chromophore.

Structural basis for the recognition of α-1,6-branched α-glucan by GH13_47 α-amylase from Rhodothermus marinus.

Glycoside hydrolase (GH) family 13 is among the main families of enzymes acting on starch; recently, subfamily 47 of GH13 (GH13_47) has been established. The crystal structure and function of a GH13_47 enzyme from Bacteroides ovatus has only been reported to date. This enzyme has α-amylase activity, while the GH13_47 enzymes comprise approximately 800-900 amino acid residues which are almost double those of typical α-amylases. It is important to know how different the GH13_47 enzymes are from other α-amylases. Rhodothermus marinus JCM9785, a thermophilic bacterium, possesses a gene for the GH13_47 enzyme, which is designated here as RmGH13_47A. Its structure has been predicted to be composed of seven domains: N1, N2, N3, A, B, C, and D. We constructed a plasmid encoding Gly266-Glu886, which contains the N3, A, B, and C domains and expressed the protein in Escherichia coli. The enzyme hydrolyzed starch and pullulan by a neopullulanase-type action. Additionally, the enzyme acted on maltotetraose, and saccharides with α-1,6-glucosidic linkages were observed in the products. Following the replacement of the catalytic residue Asp563 with Ala, the crystal structure of the variant D563A in complex with the enzymatic products from maltotetraose was determined; as a result, electron density for an α-1,6-branched pentasaccharide was observed in the catalytic pocket, and Ile762 and Asp763 interacted with the branched chain of the pentasaccharide. These findings suggest that RmGH13_47A is an α-amylase that prefers α-1,6-branched parts of starch to produce oligosaccharides.

Clinical efficacy and safety of intravenous ferric carboxymaltose for treatment of restless legs syndrome: a multicenter, randomized, placebo-controlled clinical trial.

STUDY OBJECTIVES: Iron therapy is associated with improvements in restless legs syndrome (RLS). This multicenter, randomized, double-blind study evaluated the effect of intravenous ferric carboxymaltose (FCM) on RLS. METHODS: A total of 209 adult patients with a baseline International RLS (IRLS) score ≥ 15 were randomized (1:1) to FCM (750 mg/15 mL) or placebo on study days 0 and 5. Ongoing RLS medication was tapered starting on Day 5, with the goal of discontinuing treatment or achieving the lowest effective dose. Co-primary efficacy endpoints were changed from baseline in IRLS total score and the proportion of patients rated as much/very much improved on the Clinical Global Impression (CGI)-investigator (CGI-I) scale at day 42 in the "As-Treated" population. RESULTS: The "As-Treated" population comprised 107 FCM and 101 placebo recipients; 88 (82.2%) and 68 (67.3%), respectively, completed the day 42 assessment. The IRLS score reduction was significantly greater with FCM versus placebo: least-squares mean (95% confidence interval [CI]) -8.0 (-9.5, -6.4) versus -4.8 (-6.4, -3.1); p = .0036. No significant difference was observed in the proportion of FCM (35.5%) and placebo (28.7%) recipients with a CGI-I response (odds ratio 1.37 [95% CI: 0.76, 2.47]; p = .2987). Fewer patients treated with FCM (32.7%) than placebo (59.4%) received RLS interventions between day 5 and study end (p = .0002). FCM was well tolerated. CONCLUSIONS: The IRLS score improved with intravenous FCM versus placebo, although the combination of both co-primary endpoints was not met. Potential methodological problems in the study design are discussed.

Proposed molecular mechanism of non-competitive inhibition using molecular dynamics simulations between α-glucosidase enzyme and mangostin compound as antidiabetic.

CONTEXT: Further understanding of the molecular mechanisms is necessary since it is important for designing new drugs. This study aimed to understand the molecular mechanisms involved in the design of drugs that are inhibitors of the α-glucosidase enzyme. This research aims to gain further understanding of the molecular mechanisms underlying antidiabetic drug design. The molecular docking process yielded 4 compounds with the best affinity energy, including γ-Mangostin, 1,6-dimethyl-ester-3-isomangostin, 1,3,6-trimethyl-ester-α-mangostin, and 3,6,7-trimethyl-ester-γ-mangostin. Free energy calculation with molecular mechanics with generalized born and surface area solvation indicated that the 3,6,7-trimethyl-γ-mangostin had a better free energy value compared to acarbose and simulated maltose together with 3,6,7-trimethyl-γ-mangostin compound. Based on the analysis of electrostatic, van der Waals, and intermolecular hydrogen interactions, 3,6,7-trimethyl-γ-mangostin adopts a noncompetitive inhibition mechanism, whereas acarbose adopts a competitive inhibition mechanism. Consequently, 3,6,7-trimethyl-ester-γ-mangostin, which is a derivative of γ-mangostin, can provide better activity in silico with molecular docking approaches and molecular dynamics simulations. METHOD: This research commenced with retrieving protein structures from the RCSB database, generating the formation of ligands using the ChemDraw Professional software, conducting molecular docking with the Autodock Vina software, and performing molecular dynamics simulations using the Amber software, along with the evaluation of RMSD values and intermolecular hydrogen bonds. Free energy, electrostatic interactions, and Van der Waals interaction were calculated using MM/GBSA. Acarbose, used as a positive control, and maltose are simulated together with test compound that has the best free energy. The forcefields used for molecular dynamics simulations are ff19SB, gaff2, and tip3p.

Retrogradation inhibition of starches in staple foods with maltotetraose-forming amylase.

To effectively inhibit the retrogradation of staple foods, the effects of maltotetraose-forming amylase(G4-amylase) on the short and long-term retrogradation of different staple starches such as rice starch (RS), wheat starch (WS), potato starch (PS) were studied. The results indicated that G4-amylase decreased the content of amylose. Amylose contents (21.09%) of WSG4 were higher than that (14.82%) of RSG4 and (13.13%) of PSG4. WS had the most obvious change in the chain length distribution of amylopectin. A chains decreased by 18.99% and the B1 chains decreased by 12.08% after G4-amylase treatment. Compared to RS (662 cP) and WS (693 cP), the setback viscosity of RSG4 (338 cP) and WSG4 (385 cP) decreased. Compared to RS (0.41), WS (0.45), and PS (0.51), the long-term retrogradation rate of RSG4 (0.33), WSG4 (0.31), and PSG4 (0.38) significantly reduced. It indicated that G4-amylase significantly inhibited the long-term retrogradation of WS, followed by RS and PS.

Iron Deficiency, Anemia, and Iron Supplementation in Patients With Heart Failure: A Population-Level Study.

BACKGROUND: Studies have shown an association between iron deficiency (ID) and clinical outcomes in patients with heart failure (HF), irrespective of the presence of ID anemia (IDA). The current study used population-level data from a large, single-payer health care system in Canada to investigate the epidemiology of ID and IDA in patients with acute HF and those with chronic HF, and the iron supplementation practices in these settings. METHODS: All adult patients with HF in Alberta between 2012 and 2019 were identified and categorized as acute or chronic HF. HF subtypes were determined through echocardiography data, and ID (serum ferritin concentration <100 µg/L, or ferritin concentration between 100 and 300 µg/L along with transferrin saturation <20%), and IDA through laboratory data. Broad eligibility for 3 clinical trials (AFFIRM-AHF [Study to Compare Ferric Carboxymaltose With Placebo in Patients With Acute HF and ID], IRONMAN [Intravenous Iron Treatment in Patients With Heart Failure and Iron Deficiency], and HEART-FID [Randomized Placebocontrolled Trial of Ferric Carboxymaltose as Treatment for HF With ID]) was determined. RESULTS: Among the 17 463 patients with acute HF, 38.5% had iron studies tested within 30 days post-index-HF episode (and 34.2% of the 11 320 patients with chronic HF). Among tested patients, 72.6% of the acute HF and 73.9% of the chronic HF were iron-deficient, and 51.4% and 49.0% had IDA, respectively. Iron therapy was provided to 41.8% and 40.5% of patients with IDA and acute or chronic HF, respectively. Of ID patients without anemia, 19.9% and 21.7% were prescribed iron therapy. The most common type of iron therapy was oral (28.1% of patients). Approximately half of the cohort was eligible for each of the AFFIRM-AHF, intravenous iron treatment in patients with HF and ID, and HEART-FID trials. CONCLUSIONS: Current practices for investigating and treating ID in patients with HF do not align with existing guideline recommendations. Considering the gap in care, innovative strategies to optimize iron therapy in patients with HF are required.

Maltose accumulation-induced cell death in Saccharomyces cerevisiae.

Pretreatment of lignocellulose yields a complex sugar mixture that potentially can be converted into bioethanol and other chemicals by engineered yeast. One approach to overcome competition between sugars for uptake and metabolism is the use of a consortium of specialist strains capable of efficient conversion of single sugars. Here, we show that maltose inhibits cell growth of a xylose-fermenting specialist strain IMX730.1 that is unable to utilize glucose because of the deletion of all hexokinase genes. The growth inhibition cannot be attributed to a competition between maltose and xylose for uptake. The inhibition is enhanced in a strain lacking maltase enzymes (dMalX2) and completely eliminated when all maltose transporters are deleted. High-level accumulation of maltose in the dMalX2 strain is accompanied by a hypotonic-like transcriptional response, while cells are rescued from maltose-induced cell death by the inclusion of an extracellular osmolyte such as sorbitol. These data suggest that maltose-induced cell death is due to high levels of maltose uptake causing hypotonic-like stress conditions and can be prevented through engineering of the maltose transporters. Transporter engineering should be included in the development of stable microbial consortia for the efficient conversion of lignocellulosic feedstocks.

Universal Pretreatment Development for Low-input Proteomics Using Lauryl Maltose Neopentyl Glycol.

In recent years, there has been a growing demand for low-input proteomics, particularly in the context of single-cell proteomics (SCP). In this study, we have developed a lauryl maltose neopentyl glycol (LMNG)-assisted sample preparation (LASP) method. This method effectively reduces protein and peptide loss in samples by incorporating LMNG, a surfactant, into the digestion solution and subsequently removing the LMNG simply via reversed phase solid-phase extraction. The advantage of removing LMNG during sample preparation for general proteomic analysis is the prevention of mass spectrometry (MS) contamination. When we applied the LASP method to the low-input SP3 method and on-bead digestion in coimmunoprecipitation-MS, we observed a significant improvement in the recovery of the digested peptides. Furthermore, we have established a simple and easy sample preparation method for SCP based on the LASP method and identified a median of 1175 proteins from a single HEK239F cell using liquid chromatography (LC)-MS/MS with a throughput of 80 samples per day.

Chromo-Fluorogenic Rhodamine-Based Amphiphilic Probe as a Selective and Sensitive Sensor for Intracellular Cu(I) in Living Cells.

Fluorescent probes are widely studied for metal ion detection because of their multiple favorable properties such as high sensitivity and selectivity, quick response, naked eye detection, and in situ monitoring. However, optical probes that can effectively detect the Cu(I) level in cell interiors are rare due to the difficulty associated with selectively and sensitively detecting this metal ion in a cell environment. Therefore, we designed and synthesized three water-soluble probes (1-3) with a 1,3,5-triazine core decorated by three substituents: a hydrophobic alkyl chain, a hydrophilic maltose, and a rhodamine B hydrazine fluorophore. Among the probes, probe 1, which has an octyl chain and a branched maltose group, was the most effective at sensing Cu+ in aqueous solution. Upon addition of Cu+, this probe showed a dramatic color change from colorless to pink in daylight and displayed an intense yellow fluorescence emission under 365 nm light. The limit of detection and dissociation constant (Kd) of this probe were 20 nM and 1.1 × 10-12 M, respectively, which are the lowest values reported to date. The two metal ion-binding sites and the aggregation-induced emission enhancement effect, endowed by the branched maltose group and the octyl chain, respectively, are responsible for the high sensitivity and selectivity of this probe for Cu+ detection, as demonstrated by 1H NMR, dynamic light scattering, and transmission electron microscopy studies. Furthermore, the probe successfully differentiated the Cu(I) level of cancer cells from that of the normal cells. Thus, the probe holds potential for real-time monitoring of Cu(I) level in biological samples and bioimaging of cancer cells.

Pullulanase pretreatment of highly concentrated maltodextrin solution improves maltose yield during ß-amylase-catalyzed saccharification.

Increasing the substrate concentration can effectively reduce energy consumption and result in more economic benefits in the industrial production of maltose, but this process remarkably increases the viscosity, which has a negative effect on saccharification. To improve saccharification efficiency, pullulanase is usually employed. In the conventional process of maltose production, pullulanase is added at the same time with ß-amylase or later, but this process seems inefficient when the substrate concentration is high. Herein, a novel method was introduced to enhance the maltose yield under high substrate concentration. The results indicated that the pullulanase pretreatment of highly concentrated maltodextrin solution for 2 h greatly affects the final conversion rate of ß-amylase-catalyzed saccharification. The maltose yield reached 80.95 %, which is 11.8 % above the control value. Further examination confirmed that pullulanase pretreatment decreased the number of branch points of maltodextrin and resulted in a high content of oligosaccharides. These linear chains were suitable for ß-amylase-catalyzed saccharification to produce maltose. This research offers a new effective and green strategy for starch sugar production.

Sorbitol production from mixtures of molasses and sugarcane bagasse hydrolysate using the thermally adapted Zymomonas mobilis ZM AD41.

Byproducts from the sugarcane manufacturing process, specifically sugarcane molasses (SM) and sugarcane bagasse (SB), can be used as alternative raw materials for sorbitol production via the biological fermentation process. This study investigated the production of sorbitol from SM and sugarcane bagasse hydrolysate (SBH) using a thermally adapted Zymomonas mobilis ZM AD41. Various combinations of SM and SBH on sorbitol production using batch fermentation process were tested. The results revealed that SM alone (FM1) or a mixture of SM and SBH at a ratio of 3:1 (FM2) based on the sugar mass in the raw material proved to be the best condition for sorbitol production by ZM AD41 at 37 °C. Further optimization conditions for sorbitol production revealed that a sugar concentration of 200 g/L and a CaCl2 concentration of 5.0 g/L yielded the highest sorbitol content. The maximum sorbitol concentrations produced by ZM AD41 in the fermentation medium containing SM (FM1) or a mixture of SM and SBH (FM2) were 31.23 and 30.45 g/L, respectively, comparable to those reported in the literature using sucrose or a mixture of sucrose and maltose as feedstock. These results suggested that SBH could be used as an alternative feedstock to supplement or blend with SM for sustainable sorbitol production. In addition, the fermentation conditions established in this study could also be applied to large-scale sorbitol production. Moreover, the thermally adapted Z. mobilis ZM AD41 is also a promising sorbitol-producing bacterium for large-scale production at a relatively high fermentation temperature using agricultural byproducts, specifically SM and SB, as feedstock, which could reduce the operating cost due to minimizing the energy required for the cooling system.

Biochemical and structural characterization reveals Rv3400 codes for ß-phosphoglucomutase in Mycobacterium tuberculosis.

Mycobacterium tuberculosis (Mtb) adapt to various host environments and utilize a variety of sugars and lipids as carbon sources. Among these sugars, maltose and trehalose, also play crucial role in bacterial physiology and virulence. However, some key enzymes involved in trehalose and maltose metabolism in Mtb are not yet known. Here we structurally and functionally characterized a conserved hypothetical gene Rv3400. We determined the crystal structure of Rv3400 at 1.7 Å resolution. The crystal structure revealed that Rv3400 adopts Rossmann fold and shares high structural similarity with haloacid dehalogenase family of proteins. Our comparative structural analysis suggested that Rv3400 could perform either phosphatase or pyrophosphatase or ß-phosphoglucomutase (ß-PGM) activity. Using biochemical studies, we further confirmed that Rv3400 performs ß-PGM activity and hence, Rv3400 encodes for ß-PGM in Mtb. Our data also confirm that Mtb ß-PGM is a metal dependent enzyme having broad specificity for divalent metal ions. ß-PGM converts ß-D-glucose-1-phosphate to ß-D-glucose-6-phosphate which is required for the generation of ATP and NADPH through glycolysis and pentose phosphate pathway, respectively. Using site directed mutagenesis followed by biochemical studies, we show that two Asp residues in the highly conserved DxD motif, D29 and D31, are crucial for enzyme activity. While D29A, D31A, D29E, D31E and D29N mutants lost complete activity, D31N mutant retained about 30% activity. This study further helps in understanding the role of ß-PGM in the physiology of Mtb.

Clinical effectiveness of ferric carboxymaltose (iv) versus iron sucrose (iv) in treatment of iron deficiency anaemia in pregnancy: A systematic review and meta-analysis.

BACKGROUND OBJECTIVES: Iron deficiency anaemia (IDA) during pregnancy is treated with oral and parenteral iron. The objective of this review was to compare the clinical effectiveness, safety, pregnancy and neonatal outcomes of intravenous (iv) ferric carboxymaltose (FCM) and iv iron sucrose (IS) in treating IDA in pregnancy. METHODS: The Department of Health Research funded this study. PubMed, Cochrane Library, EMBASE and Scopus were searched to include studies published till November 2022. The protocol was registered in PROSPERO (CRD42022306092). Pregnant women (15-49 yr) in second and third trimesters, diagnosed with moderate-to-severe iron deficiency anaemia, treated with either of the drugs were included. The included studies were critically assessed using appropriate tools. We conducted a qualitative synthesis of the studies and meta-analysis for improvement in haematological parameters and incidence of adverse events. RESULTS: A total of 18 studies were included. The risk of bias was low to moderate. A rise in haemoglobin up to four weeks was higher with FCM than IS by 0.57 (0.24, 0.9) g/dl. Intravenous FCM is associated with fewer adverse events than IS [pooled odds ratio: 0.5 (0.32, 0.79)]. The included studies had limited evidence on pregnancy and neonatal outcomes after iv iron treatment. INTERPRETATION CONCLUSIONS: Intravenous FCM is effective and safer than intravenous IS in terms of haematological parameters, in treating IDA in pregnancy. Further research is required on the effects of iv FCM and iv IS on the pregnancy and neonatal outcomes when used for treating IDA in pregnancy.

Co-composting sugar-containing waste with chicken manure-A new approach to carbon sequestration.

Improving resource use is a pressing research issue because of the huge potential organic waste market. Composting is a recycling technique, treatment to achieve the dual effect of resource recovery and zero waste. Waste composition varies: for example, chicken manure is rich in protein, straw contains wood fibres, fruit and vegetables contain sugar, and food waste contains starch. When considering combining waste streams for composting, it is important to ask if this approach can reduce overall composting costs while achieving a more concentrated result. Chicken manure, in particular, presents a unique challenge. This is due to its high protein content. The lack of precursor sugars for glucosamine condensation in chicken manure results in lower humus content in the final compost than other composting methods. To address this, we conducted experiments to investigate whether adding sugary fruits and vegetables to a chicken manure composting system would improve compost quality. To improve experimental results, we used sucrose and maltose instead of fruit and vegetable waste. Sugars added to chicken manure composting resulted in a significant increase in humic substance (HS) content, with improvements of 9.0% and 17.4%, respectively, compared to the control. Sucrose and maltose have a similar effect on the formation of humic substances. These results demonstrate the feasibility of composting fruit and vegetable waste with chicken manure, providing a theoretical basis for future composting experiments.