Revealing the Compact Structure of Lactic Acid Bacterial Heteroexopolysaccharides by SAXS and DLS

Molecular structures of exopolysaccharides are required to understand their functions and the relationships between the structure and physical and rheological properties. Small-angle X-ray scattering and dynamic light scattering were used in conjunction with molecular modeling to characterize solution structures of three lactic acid bacterial heteroexopolysaccharides (HePS-1, HePS-2, and HePS-3). Values of radius of gyration <i>R</i>_G, cross-sectional radius of gyration <i>R</i>_XS, approximate length <i>L</i>, and hydrodynamic diameter were not directly proportional to the molar mass and indicated the HePSs adopted a compact coil-like rather than an extended conformation. Constrained molecular modeling of 15000 randomized HePS-1 conformers resulted in five best-fit structures with <i>R</i> factor of 3.9−4.6% revealing random coil-like structure. Φ and Ψ angle analysis of glycosidic linkages in HePS-1 structures suggests Gal<i>f</i> residues significantly influence the conformation. Ab initio scattering modeling of HePS-2 and HePS-3 gave excellent curve fittings with χ² of 0.43 and 0.34 for best-fit models, respectively, compatible with coil-like conformation. The findings disclose solution behavior of HePS relevant for their interactions with biomacromolecules, for example, milk proteins

Insect biomass shows a stronger decrease than species richness along urban gradients

1. Anthropogenic land cover change is a major driver of biodiversity loss, with urbanisation and farmland practices responsible for some of the most drastic modifications of natural habitats. The relative importance of different land covers for shaping insect communities, however, is unclear. 2. This study examines the effect of urban and farmland covers, along with land cover heterogeneity, at a landscape scale on species richness, evenness and biomass of flying insects using citizen science carnet sampling across Denmark. 3. Increasing urban cover had a negative effect on insect richness but an even stronger negative effect on biomass. Increased land cover heterogeneity did not mitigate the negative effect of urban cover. Insect assemblages also became more even with increased urban cover. Farmland cover had no significant effect on insect richness, evenness or biomass. 4. Based on our findings, the urban cover has a strong negative impact on insect communities, indicating that urbanisation could contribute to insect declines. Moreover, our findings indicate that insect loss occurs more through loss of biomass than loss of species, which may affect the ecosystem-level consequences of urbanisation

Interaction between structurally different heteroexopolysaccharides and β-lactoglobulin studied by solution scattering and analytical ultracentrifugation

Predmet ovog rada je Lean proizvodnja-korak ka uspjehu. Lean proizvodnje naglašava minimiziranje količine resursa koji se koriste u raznim aktivnostima kompanije i uključuje identificiranje i eliminiranje aktivnosti koje ne donosi vrijednost. Filozofija Lean proizvodnje uključuje principe i praksu smanjivanja troškova kroz uklanjanje "otpada" i kroz pojednostavljenje svih aktivnosti kompanije. Postoji sedam vrsta tradicionalnih otpada u aktivnostima kompanije i više od desetak alata za njihovo uklanjanje. U postizanju filozofije Lean proizvodnje pet je glavnih koraka koji označavaju životni ciklus racionalne proizvodnje. Lean proizvodnja i filozofija racionalnog poslovanja omogućava kompanijama da budu bolje, brže, njihovi proizvodi i/ili usluge jeftinije, a one same privlačnije kupcima.The subject of this paper is Lean production-step to success. Lean Production highlights the minimization of the amount of resources used in the company's various activities and involves identifying and eliminating activities that do not bring value. The Lean manufacturing philosophy includes the principles and practice of reducing costs through the removal of "waste" and simplifying all company activities. There are seven types of traditional waste in the company's activities and more than a dozen tools for their removal. In achieving the Lean production philosophy, five major steps are to be found that indicate the life cycle of rational production. Lean manufacturing and the philosophy of rational business enable companies to be better, faster, their products and/or services cheaper, and those more attractive to customers

Autochthonous heritage languages and social media:writing and bilingual practices in Low German on Facebook

This article analyses how speakers of an autochthonous heritage language (AHL) make use of digital media, through the example of Low German, a regional language used by a decreasing number of speakers mainly in northern Germany. The focus of the analysis is on Web 2.0 and its interactive potential for individual speakers. The study therefore examines linguistic practices on the social network site Facebook, with special emphasis on language choice, bilingual practices and writing in the autochthonous heritage language. The findings suggest that social network sites such as Facebook have the potential to provide new mediatized spaces for speakers of an AHL that can instigate sociolinguistic change

Inactivation of murine norovirus by chemical biocides on stainless steel

<p>Abstract</p> <p>Background</p> <p>Human norovirus (NoV) causes more than 80% of nonbacterial gastroenteritis in Europe and the United States. NoV transmission via contaminated surfaces may be significant for the spread of viruses. Therefore, measures for prevention and control, such as surface disinfection, are necessary to interrupt the dissemination of human NoV. Murine norovirus (MNV) as a surrogate for human NoV was used to study the efficacy of active ingredients of chemical disinfectants for virus inactivation on inanimate surfaces.</p> <p>Methods</p> <p>The inactivating properties of different chemical biocides were tested in a quantitative carrier test with stainless steel discs without mechanical action. Vacuum-dried MNV was exposed to different concentrations of alcohols, peracetic acid (PAA) or glutaraldehyde (GDA) for 5 minutes exposure time. Detection of residual virus was determined by endpoint-titration on RAW 264.7 cells.</p> <p>Results</p> <p>PAA [1000 ppm], GDA [2500 ppm], ethanol [50% (v/v)] and 1-propanol [30% (v/v)] were able to inactivate MNV under clean conditions (0.03% BSA) on the carriers by ≥ 4 log₁₀within 5 minutes exposure time, whereas 2-propanol showed a reduced effectiveness even at 60% (v/v). Furthermore, there were no significant differences in virus reduction whatever interfering substances were used. When testing with ethanol, 1- and 2-propanol, results under clean conditions were nearly the same as in the presence of dirty conditions (0.3% BSA plus 0.3% erythrocytes).</p> <p>Conclusion</p> <p>Products based upon PAA, GDA, ethanol and 1-propanol should be used for NoV inactivation on inanimate surfaces. Our data provide valuable information for the development of strategies to control NoV transmission via surfaces.</p

Infektionsquellensuche bei ambulant erworbenen Fällen von Legionärskrankheit – Ergebnisse der LeTriWa-Studie; Berlin, 2016 – 2020 – Teil 2 (Ergebnisse und Diskussion)

Im Rahmen der Berliner LeTriWa-Studie („Legionellen in der Trinkwasser-Installation“) versuchten wir, ambulant erworbene Fälle von Legionärskrankheit (AE-LK) evidenzbasiert einer Infektionsquelle zuzuordnen. Dafür wurde eine eigens entwickelte Evidenz-Matrix genutzt, mit der die Fälle anhand von drei Evidenztypen (mikrobiologische Evidenz, Cluster-Evidenz und analytisch-vergleichende Evidenz) entweder einer externen Infektionsquelle, einer häuslichen Nicht-Trinkwasserquelle (hNTWQuelle) oder häuslichem Trinkwasser (hTW) zugeordnet werden konnten. Wir rekrutierten 147 Studienteilnehmende (LeTriWa-Fälle) sowie 217 Kontrollpersonen als Vergleichsgruppe. Bei 84 LeTriWa- Fällen konnte aus den Patientenproben der monoklonale Antikörpertyp (MAb) identifiziert werden, bei 83 (99 %) ein MAb 3/1-positiver Stamm und bei einem Fall ein MAb 3/1-negativer Stamm. Im Vergleich zu den Kontrollpersonen war der Fallstatus (infiziert vs. nicht infiziert) nicht mit einer höheren Legionellenkonzentration in den Standard-Haushaltswasserproben assoziiert, die bei Fällen und Kontrollen in gleicher Weise genommen worden waren. Wir fanden jedoch eine hochsignifikante Assoziation mit dem Vorhandensein eines MAb 3/1-positiven Stammes in den Standard-Haushaltsproben. Wir konnten etwa für die Hälfte der LeTriWa-Fälle evidenzbasiert eine wahrscheinliche Quelle zuordnen, und zwar 23 (16 %) einer externen Infektionsquelle, 9 (6 %) einer hNTW-Quelle und 40 (27 %) dem hTW.Peer Reviewe