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Zalewski, M.

Publications and source records attributed to Zalewski, M..

3 recordsLinked to original sources

High-temporal resolution of microbial food web dynamics and structure during phytoplankton blooms in the Baltic Sea

Heterotrophic nanoflagellates (HNF) are a key component of the microbial food webs, playing an essential role in nutrient recycling and energy transfer in aquatic ecosystems. They have been typically considered to be bacterivores, but they can be also omnivorous (feeding on prokaryotes and other eukaryotes) and predatory grazers (feeding on other eukaryotes). Here, we combine CARD-FISH with both short and long-amplicon sequencing to resolve dynamics of key HNF groups during two high-frequency sampling campaigns in spring (March-May) and autumn (September-November) phytoplankton blooms in the coastal waters of the Baltic Sea. This approach allowed us to resolve the microbial food web dynamics within HNF communities at the phylotype level at time scales relevant to HNF duplication times. Omnivorous katablepharids and predatory MAST-2 dominated the HNF community, especially in spring. Bacterivorous groups (e.g., MAST-1, CRY1) were less abundant. Long-read sequencing revealed distinct seasonal shifts in dominant phylotypes, with Katablepharis sp. and MAST-2D peaking in spring, while other lineages became more prominent in summer and autumn. The high abundance of omnivorous HNF, compared to bacterivores, highlights their key role both as grazers of bacteria and flagellates and as a food source for predatory and omnivorous ciliates. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=193 SRC="FIGDIR/small/676335v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@c4ec55org.highwire.dtl.DTLVardef@77fd5dorg.highwire.dtl.DTLVardef@19b237borg.highwire.dtl.DTLVardef@368f39_HPS_FORMAT_FIGEXP M_FIG C_FIG

ecology↗

Flexible docking of cyclic peptides to proteins using CABS-dock

Cyclic peptides are promising therapeutics, but their flexible docking remains challenging. We present a protocol based on the well-established CABS-dock method, enhanced with cyclic restraints and Rosetta refinement. The approach was evaluated on 38 benchmark complexes previously used in other docking method studies. While selecting the truly best model remains difficult, near-native solutions are frequently sampled. CABS-dock offers global, unbiased docking without prior binding site knowledge, making it valuable for pose generation, structural ensemble modeling, and integration into AI-driven peptide-protein docking workflows.

bioinformatics↗

Protein-protein docking with large-scale backbone flexibility

Most of the protein-protein docking methods treat proteins as almost rigid objects. Only the side-chains flexibility is usually taken into account. The few approaches enabling docking with a flexible backbone typically work in two steps, in which the search for protein-protein orientations and structure flexibility are simulated separately. In this work, we propose a new straightforward approach for docking sampling. It consists of a single simulation step during which a protein undergoes large-scale backbone rearrangements, rotations, and translations. Simultaneously, the other protein exhibits small backbone fluctuations. Such extensive sampling was possible using the CABS coarse-grained protein model and Replica Exchange Monte Carlo dynamics at a reasonable computational cost. In our proof-of-concept simulations of 62 protein-protein complexes, we obtained acceptable quality models for a significant number of cases.

bioinformatics↗