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Sulfoquinovose (SQ, 6-deoxy-6-sulfoglucose) is a sulfosugar that is the anionic head group of plant, algal, and cyanobacterial sulfolipids: sulfoquinovosyl diacylglycerols. SQ is produced within photosynthetic tissues, forms a major terrestrial reservoir of biosulfur, and is an important species within the biogeochemical sulfur cycle. A major pathway for SQ breakdown is the sulfoglycolytic Embden-Meyerhof-Parnas pathway, which involves cleavage of the 6-carbon chain of the intermediate sulfofructose-1-phosphate (SFP) into dihydroxyacetone and sulfolactaldehyde, catalyzed by class I or II SFP aldolases. While the molecular basis of catalysis is understood for class I SFP aldolases, comparatively little is known about class II SFP aldolases. Here, we report the molecular architecture and biochemical basis of catalysis of two metal-dependent class II SFP aldolases from Hafnia paralvei and Yersinia aldovae. 3D X-ray structures of complexes with substrate SFP and product dihydroxyacetone phosphate reveal a dimer-of-dimers (tetrameric) assembly, the sulfonate-binding pocket, two metal-binding sites, and flexible loops that are implicated in catalysis. Both enzymes were metal-dependent and exhibited high K M values for SFP, consistent with their role in a unidirectional nutrient acquisition pathway. Bioinformatic analysis identified a range of sulfoglycolytic Embden-Meyerhof-Parnas gene clusters containing class I/II SFP aldolases. The class I and II SFP aldolases have mututally exclusive occurrence within Actinobacteria and Firmicutes phyla, respectively, while both classes of enzyme occur within Proteobacteria. This work emphasizes the importance of SQ as a nutrient for diverse bacterial phyla and the different chemical strategies they use to harvest carbon from this sulfosugar., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Nowadays there are numerous studies on the occurrence of cognitive dysfunction in late-life depression (LLD). The role of executive dysfunctions in the psychopathology of depression is particularly emphasized and needs further examination. The aim was to assess cognitive functions and their relation to depressive symptoms in elders with LLD, previously depressed, and patients without the history of depressive episodes. The study consisted of 824 older adults who underwent a neuropsychological evaluation (97 currently depressed, 114 previously depressed and 613 patients without the history of depressive episodes). LLD patients performed poorer in ACE-III and AVLT and poorer in TMT-B than those previously depressed and never depressed. The LLD group also performed significantly poorer than the previously depressed on Digit Span Forward. Results of a multiple regression analysis indicated that performance on measures of executive functioning was associated with depression severity in LLD (β =.227, P =.024). The results of this study suggest that executive functions are the most impaired in the elderly with LLD. Furthermore, there is a relationship between executive dysfunction and the severity of depression in LLD. Executive dysfunction appears to be the core neurocognitive deficit in LLD.

Background: Empathy plays the key role in the doctor - patient relationship. The research of empathy determinants plays an important role in formulating practical guidelines for the education of medical students. The aim of this study was to analyse personality characteristics of empathy profiles among students of medicine, with consideration of chief personality factors and their subdimensions according to the FFM model., Methods: During workshops in Clinical Psychological Skills, 153 students (M = 57, F = 96; mean age 23 years) analysed their psychological functioning styles by examining their personality profiles and empathy indicators. Empathic Sensitiveness Scale (ESS) and Personality Inventory (NEO-PI-R) were applied for this purpose. The analyses of empathy indicators were presented by means of cluster analysis. Variance analysis with post hoc Tukey-b test was performed for differences between clusters and to differentiate between personality factors and their components in empathy clusters. This study was approved by the Jagiellonian University Bioethics Committee (approval number: 1072.6120.175.2018 date: 28.06.2018)., Results: The first cluster included students who presented high empathetic concern for others, understood their perspective and needs characterised by medium level of Neuroticism, high levels of other dimensions The second group included students who could understand others very well, yet with lower tendency to react emotionally to suffering, characterised by medium level of Neuroticism, Extraversion, Openness, high Conscientiousness and low Agreeableness. The third cluster included students who react strongly to painful and unpleasant reactions of others, characterised by high Neuroticism and Agreeableness, low Extraversion., Conclusions: Each empathy profile is manifested in relations with patients in a specific way. Medical education in empathy holds great potential to reduce anxiety, stress, and burnout associated with the medical profession. Discussion of individual results with students, gives an opportunity to talk about how their empathy and personality characteristics may influence their everyday medical practice., (© 2022. The Author(s).)

Sulfoquinovose (SQ) is the anionic headgroup of the ubiquitous plant sulfolipid, sulfoquinovosyl diacylglycerol (SQDG). SQDG can undergo delipidation to give sulfoquinovosyl glycerol (SQGro) and further glycoside cleavage to give SQ, which can be metabolized through microbial sulfoglycolytic pathways. Exogenous SQDG metabolites are imported into bacteria through membrane spanning transporter proteins. The recently discovered sulfoglycolytic sulfoquinovose monooxygenase (sulfo-SMO) pathway in Agrobacterium tumefaciens features a periplasmic sulfoquinovosyl glycerol binding protein, SmoF, and an ATP-binding cassette (ABC) transporter. Here, we use X-ray crystallography, differential scanning fluorimetry and isothermal titration calorimetry to study SQ glycoside recognition by SmoF. This work reveals that in addition to SQGro, SmoF can also bind SQ, a simple methyl glycoside and even a short-chain SQDG analogue. Molecular recognition of these substrates is achieved through conserved interactions with the SQ-headgroup together with more plastic interactions with the aglycones. This suggests that the solute binding protein of A. tumefaciens, and related SQ-binding proteins from other sulfoglycolytic pathways, can provide their host organisms direct access to most of the SQ metabolites known to be produced by phototrophs., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors.)

Catabolism of sulfoquinovose (SQ; 6-deoxy-6-sulfoglucose), the ubiquitous sulfosugar produced by photosynthetic organisms, is an important component of the biogeochemical carbon and sulfur cycles. Here, we describe a pathway for SQ degradation that involves oxidative desulfurization to release sulfite and enable utilization of the entire carbon skeleton of the sugar to support the growth of the plant pathogen Agrobacterium tumefaciens SQ or its glycoside sulfoquinovosyl glycerol are imported into the cell by an ATP-binding cassette transporter system with an associated SQ binding protein. A sulfoquinovosidase hydrolyzes the SQ glycoside and the liberated SQ is acted on by a flavin mononucleotide-dependent sulfoquinovose monooxygenase, in concert with an NADH-dependent flavin reductase, to release sulfite and 6-oxo-glucose. An NAD(P)H-dependent oxidoreductase reduces the 6-oxo-glucose to glucose, enabling entry into primary metabolic pathways. Structural and biochemical studies provide detailed insights into the recognition of key metabolites by proteins in this pathway. Bioinformatic analyses reveal that the sulfoquinovose monooxygenase pathway is distributed across Alpha- and Betaproteobacteria and is especially prevalent within the Rhizobiales order. This strategy for SQ catabolism is distinct from previously described pathways because it enables the complete utilization of all carbons within SQ by a single organism with concomitant production of inorganic sulfite., Competing Interests: The authors declare no competing interest., (Copyright © 2022 the Author(s). Published by PNAS.)