Mathematical Models of Microbial Evolution: Cooperative Systems

Microbes usually live in large communities, where they interact with other organisms and species. These interactions include cooperation, when individuals facilitate each others growth and reproduction. Such cooperation has been for instance observed within pathogens in the process of infection. Therefore, given the number and the frequency of infectious diseases, understanding the nature and the dynamics of microbial cooperation may be a crucial step in modern medicine. Microbes often secrete costly enzymes which extracellularly metabolise resources available in the environment. This external metabolism is a form of ’public good cooperation’, in which individuals invest their energy in producing ’public goods’, available to other organisms. To study this phenomenon we deploy mathematical models which are based on biologically relevant assumptions. Our models not only aim to capture the dynamics of studied microbial communities, but also to remove the natural complexity arising in the empirical studies and thus to provide a mechanistic understanding of their results. We first recover and explain the recent empirical finding, about mixed strain infections, showing that an addition of a low virulent strain which does not produce public goods (termed ’cheat’) may counter-intuitively enhance the total population virulence. What drives this result turns out to be an interaction of two different cooperative traits and the presence of spatial structure. Next we study the competition between the strains that do and do not produce public goods. Our results depend on environmental conditions, such as resource concentration and population density, but they are also determined by the degree of spatial structure - the ecological trait which so far has been treated only as a binary variable. Finally, we identify some environmental threats for the external metabolism feeding strategy, and we examine its competitiveness in comparison to ’internal metabolism’, in which the costly enzymes are private.EPSR

The UNITE database for molecular identification and taxonomic communication of fungi and other eukaryotes : sequences, taxa and classifications reconsidered

Acknowledgements We acknowledge Marie Zirk for her work in designing the UNITE logotype and creating the visual abstract for this article. Funding UNITE database development is financed by the Estonian Research Council [PRG1170]; European Union's Horizon 2020 project BGE [101059492]. The PlutoF digital infrastructure is supported by the European Union's Horizon 2020 project BiCIKL [101007492]; Estonian Research Infrastructure roadmap project DiSSCo Estonia. Funding for open access charge: UNITE Community. Conflict of interest statement. None declared.Peer reviewedPublisher PD

FungalTraits:A user-friendly traits database of fungi and fungus-like stramenopiles

The cryptic lifestyle of most fungi necessitates molecular identification of the guild in environmental studies. Over the past decades, rapid development and affordability of molecular tools have tremendously improved insights of the fungal diversity in all ecosystems and habitats. Yet, in spite of the progress of molecular methods, knowledge about functional properties of the fungal taxa is vague and interpretation of environmental studies in an ecologically meaningful manner remains challenging. In order to facilitate functional assignments and ecological interpretation of environmental studies we introduce a user friendly traits and character database FungalTraits operating at genus and species hypothesis levels. Combining the information from previous efforts such as FUNGuild and Fun(Fun) together with involvement of expert knowledge, we reannotated 10,210 and 151 fungal and Stramenopila genera, respectively. This resulted in a stand-alone spreadsheet dataset covering 17 lifestyle related traits of fungal and Stramenopila genera, designed for rapid functional assignments of environmental studies. In order to assign the trait states to fungal species hypotheses, the scientific community of experts manually categorised and assigned available trait information to 697,413 fungal ITS sequences. On the basis of those sequences we were able to summarise trait and host information into 92,623 fungal species hypotheses at 1% dissimilarity threshold

Matching on individual and relational variables differentially predicts (satisfaction with) intimate behaviors in men and women - a daily diary study

Pawlowska A, Norget J, Janssen E, Dewitte M. Matching on individual and relational variables differentially predicts (satisfaction with) intimate behaviors in men and women - a daily diary study. In: Proceedings of the 2022 Meeting of the International Society for the Study of Women's Sexual Health . Journal of Sexual Medicine. Vol 19. New York: Elsevier; 2022: S113.Objectives Intimate behaviors, including cuddling, kissing, and genital touch, are interpersonal phenomena that are dependent on characteristics of the relationship as well as partners’ responses. Yet research on this topic typically relies on individual reports and does not account for interpersonal processes. In this study, we investigated how matching between heterosexual partners on relationship satisfaction and the extent to which they had sexual thoughts during the day, rather than their individual scores, may affect each partner's (satisfaction with) intimate behaviors. Methods Over the course of 21 days, 66 couples submitted daily reports on their (satisfaction with) intimate behaviors, and the extent to which they had sexual thoughts the previous day (every morning), and on their relationship satisfaction during the day (every evening). We estimated actor, partner, and within-couple agreement effects, as well as change, and daily variability. We examined both the magnitude and direction of matching in partner's evaluations and thoughts, while accounting for dependency within couples. Results Results showed that for women, matching on moderate levels of relationship satisfaction was associated with lower intimacy satisfaction than matching on extreme levels of relationship satisfaction, and matches were associated with lower intimacy satisfaction than mismatches. For both men and women, stronger matching on sexual thoughts between partners was associated with more (satisfaction with) intimate behaviors, and matching was better than mismatching. When men had more sexual thoughts during the day than their female partners this was associated with more intimate behaviors, and more intimacy satisfaction. Conclusions These results provide support for a dynamical relationship between individual and relational variables associated with intimacy and intimacy satisfaction in couples. They also show the nuanced way in which relational and sexual variables influence each other on a day-to-day basis, highlighting the need to develop interpersonal models of intimacy and sex that account for the dyadic interaction between partners

Lysine-based amino-functionalized lipids for gene transfection: 3D phase behaviour and transfection performance

Based on previous work, the influence of the chain composition on the physical–chemical properties of five new transfection lipids (TH10, TT10, OH10, OT10 and OO10) containing the same lysine-based head group has been investigated in aqueous dispersions. For this purpose, the chain composition has been gradually varied from saturated tetradecyl (T, C$_{14:0}$) and hexadecyl (H, C$_{16:0}$) chains to longer but unsaturated oleyl (O, C$_{18:1}$) chains with double bonds in the cis configuration. In this work, the lipid dispersions have been investigated in the absence and presence of the helper lipid DOPE and calf thymus DNA by small-angle and wide-angle X-ray scattering (SAXS/WAXS) supplemented by differential scanning calorimetry (DSC), attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) and Fourier-transform Raman spectroscopy (FTRS). Lamellar and inverted hexagonal mesophases have been observed in single-component systems. In the binary mixtures, the aggregation behaviour changes with an increasing amount of DOPE from lamellar to cubic. The lipid mixtures with DNA show a panoply of mesophases. Interestingly, TT10 and OT10 form cubic lipoplexes, whereas OO10 complexes the DNA sandwich-like between lipid bilayers in a lamellar lipoplex. Surprisingly, the latter is the most effective lipoplex