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Pickering, I.

Publications and source records attributed to Pickering, I..

2 recordsLinked to original sources

BitBIRCH-Lean: chemical space in the palm of your workstation

We present BitBIRCH-Lean, a fast, memory-efficient implementation of the Bit-BIRCH algorithm, designed for high-throughput clustering of huge molecular libraries (up to billions of drug-like molecules) on typical workstations. BitBIRCH-Lean considerably improves on the original BitBIRCH implementation by incorporating dynamic types and bit-packed fingerprints inside the clustering tree. Most operations in BitBIRCH-Lean are efficiently performed on compressed data, and optional C++ extension accelerate the bottleneck calculations, providing up to 2X speedup. Benchmark tests against GPU-accelerated methods highlight BitBIRCH-Lean as an efficient alternative for processing vast amounts of molecules. We further demonstrate the versatility of this new package by showcasing a parallel, multi-round variant of the Bit- BIRCH algorithm that exploits the gains in efficiency to cluster hundreds of millions of molecules in minutes, with no loss in cluster quality. The code is freely available at: https://github.com/mqcomplab/bblean.

bioinformatics↗

PIN FORMED 2 facilitates the transport of Arsenite in Arabidopsis thaliana

Arsenic contamination is a major environmental issue as it may lead to serious health hazard. Reduced trivalent form of inorganic arsenic, arsenite, is in general more toxic to plants compared with the fully oxidized pentavalent arsenate. The uptake of arsenite in plants has been shown to be mediated through a large subfamily of plant aquaglyceroporins, nodulin 26-like intrinsic proteins (NIPs). However, the efflux mechanisms, as well as the mechanism of arsenite-induced root growth inhibition, remain poorly understood. Using molecular physiology, synchrotron imaging, and root transport assay approaches, we show that the cellular transport of trivalent arsenicals in Arabidopsis thaliana is strongly modulated by PIN FORMED 2 (PIN2) auxin efflux transporter. Direct transport assay using radioactive arsenite, X-ray fluorescence imaging (XFI) coupled with X-ray absorption spectroscopy (XAS), and ICP-MS analysis revealed that pin2 plants accumulate higher concentrations of arsenite in root compared to wild-type. At the cellular level, arsenite specifically targets intracellular cycling of PIN2 and thereby alters the cellular auxin homeostasis. Consistently, loss of PIN2 results in aresenite hypersensitivity in root. XFI coupled with XAS further revealed that loss of PIN2 results in specific accumulation of arsenical species, but not the other metals like iron, zinc or calcium in the root tip. Collectively, these results demonstrate that PIN2 serves as a putative transporter of arsenical species in planta.

plant biology↗