Biology subjects

Brander, S.

Publications and source records attributed to Brander, S..

4 recordsLinked to original sources

bioRxiv2022

A seven transmembrane-integral methyltransferase catalysing N-terminal histidine methylation of lytic polysaccharide monooxygenases

Lytic polysaccharide monooxygenases (LPMOs) are oxidative enzymes that help break down lignocellulose, making them highly attractive for improving biomass utilization in biotechnological purposes. The catalytically essential N-terminal histidine (His1) of LPMOs is post-translationally modified by methylation in filamentous fungi to protect them from auto-oxidative inactivation, however, the responsible methyltransferase enzyme is unknown. Using mass-spectrometry-based quantitative proteomics in combination with systematic CRISPR/Cas9 knockout screening in Aspergillus nidulans, we identified the N-terminal histidine methyltransferase (NHMT) encoded by the gene AN4663. Targeted proteomics confirmed that NHMT was solely responsible for His1 methylation of LPMOs. NHMT is predicted to encode a unique seven-transmembrane segment anchoring a soluble methyltransferase domain. Co-localization studies showed endoplasmic reticulum residence of NHMT and co-expression in the industrial production yeast Komagataella phaffii with LPMOs resulted in His1 methylation of the LPMOs. This demonstrates the biotechnological potential of recombinant production of proteins and peptides harbouring this unique post-translational modification.

molecular biology↗

bioRxiv2021

Targeting activated macrophages intracellular milieu to augment anti-inflammatory drug potency

We present pH-responsive phosphorylcholine polymersomes ability to target activated macrophages via scavenger receptors, enter them via endocytosis, and escape from early endosomes enabling the intra-cellular drug delivery. Using an arthritis experimental model and the gold standard disease modifying anti-rheumatic drug, methotrexate, we prove that polymersomes augments therapeutic efficacy, while minimizing the off-target effect. First, we demonstrate the selective accumulation of polymersomes within the inflamed synovial tissues and cells, including macrophages. Second, we show the beneficial therapeutic effect of methotrexate loaded polymersomes in preventing both joint inflammation and further damage. Hence, we prove the therapeutic potential of polymersomes in enhancing the complete prevention of arthritis progression, which makes it a promising nanotherapy for arthritis treatment as well as other inflammatory disorders. TeaserWe show that the effective targeting and delivery of drugs to the main inflammation actors, the macrophages, enhances arthritis therapy.

immunology↗

bioRxiv2020

LyGo: A platform for rapid screening of lytic polysaccharide monooxygenase production

Environmentally friendly sources of energy and chemicals are essential constituents of a sustainable society. An important step towards this goal is the utilization of non-edible biomass as supply of building blocks for future biorefineries. Lytic polysaccharide monooxygenases (LPMOs) are enzymes that play a critical role in breaking the chemical bonds in the most abundant polymers found in recalcitrant biomass, such as cellulose and chitin. Predicting optimal strategies for producing LPMOs is often non-trivial, and methods allowing for screening several strategies simultaneously are therefore needed. Here, we present a standardized platform for cloning LPMOs. The platform allows users to combine gene fragments with different expression vectors in a simple 15-minute reaction, thus enabling rapid exploration of several gene contexts, hosts and expression strategies in parallel. The open-source LyGo platform is accompanied by easy-to-follow online protocols for both cloning and expression. As a demonstration, we utilize the LyGo platform to explore different strategies for expressing several different LPMOs in Escherichia coli, Bacillus subtilis, and Komagataella phaffii.

bioengineering↗

bioRxiv2019

Proof-of-concept for the detection of early osteoarthritis pathology by endomicroscopy

Osteoarthritis (OA) is a degenerative joint disease and the leading cause of global disability. Clinical trials to date have been unable to pinpoint early and potentially reversible disease states with current clinical technology and hence disease-modifying OA drug candidates cannot be tested early in the disease. To overcome this obstacle, we correlate articular cartilage stiffness changes and cellular spatial organization. The former is a well-understood and functionally relevant OA pathology, while the latter allows discriminating between healthy vs early OA, based on distinct cellular spatial patterns. We demonstrated that an extensive loss of atomic force microscopy-detected stiffness can be seen in cartilage tissues with spatial patterns exhibiting the earliest identifiable OA. In addition, the translation of commercially available clinically usable probe-based confocal laser-endomicroscopy allows us to detect these early OA spatial patterns. This study resolves a major clinical trial obstacle by presenting the proof-of-concept that early OA pathology can be detected by already available clinical technology.\n\nOne Sentence SummaryWe report a correlation between articular cartilage surface nanoscale stiffness and chondrocyte spatial organization; using this correlation enables early pathology detection by currently available clinical optical methods.

biophysics↗