Biology subjects

Man, T.

Publications and source records attributed to Man, T..

4 recordsLinked to original sources

bioRxiv2025

Stimuli-Expressed Protein Qubits for Quantum Quantification of Heavy Metals in Natural Water

Environmental heavy metal pollution poses a severe threat to ecological security and human health, necessitating the development of highly sensitive, specific, and rapid detection technologies. Traditional fluorescent biosensors are often constrained by high background interference and limited sensitivity, while single-target detection systems struggle to meet the demands of complex environmental monitoring. This study constructs a novel magnetically modulated photonic quantum biosensing system based on the CadC-T7 gene circuit, replacing the traditional fluorescent reporter gene EGFP with the magnetically modulated fluorescent protein MagLOV - a quantum biomaterial. To enhance its magnetic modulation performance, the mutant with the highest lock-in amplitude during the directed evolution (R10, MagLOV 2) was selected; Simultaneously, systematic parameter optimization was conducted to determine the optimal magnetic modulation frequency (0.05 Hz), the heavy metal stimulation duration (the 2-hour group exhibited the most significant intra-group variation), and the bacterial concentration at the onset of the heavy metal stimulation (controlled at OD600 = 1 to prevent fluorescence quenching due to culture turbidity). The system demonstrates excellent multi-analyte detection capabilities for lead chloride, lead nitrate, and cadmium chloride across a concentration range of 10-8 to 10-4 M. Compared to conventional steady-state photometric methods based on EGFP and MagLOV 2, the lock-in analysis of MagLOV 2 achieves detection sensitivities enhanced by 1[~]2 orders of magnitude, with detection limits as low as 2.4 nM for cadmium chloride, 4.8 nM for lead nitrate, and 9.9 nM for lead chloride. Langmuir isotherm fitting results demonstrate high quantitative accuracy (R2 > 0.950), with particularly outstanding fitting performance for cadmium chloride (R2 = 0.999) and lead nitrate (R2 = 0.995).

synthetic biology↗

bioRxiv2024

Geographic variation in vulnerability to warming temperatures in an intertidal barnacle species

Vulnerability to warming temperatures under climate change arises when there is a gap between local climate and local physiology. Intertidal species are unique because they face two distinct thermal environments, and it is unclear which is the bigger driver of thermal physiology and vulnerability. Here we compare the thermal environments and physiology of three populations of the intertidal barnacle Balanus glandula, spanning 1460 km of its geographic range. We measured energy consumption in the laboratory across a 5-hour emersion and subsequent 6-hour immersion at 7 different emersion temperatures (10-38{degrees}C). We compared these results to one year of emersion and immersion temperature data from each location. Our results suggest that the temperatures experienced during emersion are a bigger driver of each populations emersion thermal physiology than those experienced during immersion. We also estimated vulnerability to future warming in two ways: as the total annual energy demand and as the number of days above each populations thermal peak. These produced conflicting results. The central population spent the most days over its thermal peak, but the northernmost population had the greatest total costs over a year. The higher energetic costs in the northernmost population may be explained in part by a strong latitudinal gradient in primary productivity that is selecting for higher energy demand in higher latitude populations. Thus, accurate predictions of B. glandulas response to warming temperatures will require knowledge of both future temperature and food availability.

ecology↗

bioRxiv2023

Massively Concurrent Sub-Cellular Traction Force Videography enabled by Single-Pixel Optical Tracers (SPOTs)

We report a large field-of-view and high-speed videography platform for measuring the sub-cellular traction forces of more than 10,000 biological cells over 13mm2 at 83 frames per second. Our Single-Pixel Optical Tracers (SPOT) tool uses 2-dimensional diffraction gratings embedded into a soft substrate to convert cells mechanical traction stress into optical colors detectable by a video camera. The platform measures the sub-cellular traction forces of diverse cell types, including tightly connected tissue sheets and near isolated cells. We used this platform to explore the mechanical wave propagation in a tightly connected sheet of Neonatal Rat Ventricular Myocytes (NRVMs) and discovered that the activation time of some tissue regions are heterogeneous from the overall spiral wave behavior of the cardiac wave. One-Sentence SummaryAn optical platform for fast, concurrent measurements of cell mechanics at 83 frames per second, over a large area of 13mm2.

bioengineering↗

bioRxiv2020

Stable transplantation of human mitochondrial DNA by high-throughput, pressurized mitochondrial delivery

Generating mammalian cells with specific mtDNA-nDNA combinations is desirable but difficult to achieve and would be enabling for studies of mitochondria-nucleus communication and coordination in controlling cell fates and functions. We developed MitoPunch, a force-actuated mitochondrial transfer device, to deliver isolated mitochondria into numerous target mammalian cells simultaneously. MitoPunch and MitoCeption, an alternative force-based mitochondrial transfer approach, both yield stable isolated mitochondrial recipient (SIMR) cells that permanently retain exogenous mtDNA, whereas coincubation of mitochondria with cells does not yield SIMR cells. Although a typical MitoPunch or MitoCeption delivery results in dozens of immortalized SIMR clones with restored oxidative phosphorylation, only MitoPunch can produce replication-limited, non-immortal human SIMR clones. The MitoPunch device is versatile, inexpensive to assemble, and easy to use for engineering mtDNA-nDNA combinations to enable fundamental studies and potential translational applications.

cell biology↗