@article{lu_wang_yuan_2024, title={ILLUMINATION EFFECTS ON BACTERIORHODOPSIN ACCUMULATION IN ARCHAEON <i>HALOBACTERIUM HALOBIUM</i>}, volume={67}, ISSN={["2769-3287"]}, DOI={10.13031/ja.15349}, abstractNote={Highlights Effects of varying illumination conditions, including light intensity, light color, and illumination pattern on archaeon Halobacterium halobium growth and bacteriorhodopsin (BR) accumulation were first evaluated. LED green light was much more energy-efficient than the red and blue lights in this research. If energy consumption was not a concern, LED blue and red lights (or their combinations) were more effective for cell growth and BR accumulation, respectively, with a similar light intensity. Abstract. This study was to understand the effect of LED light intensity, color, and illumination pattern on the growth of and bacteriorhodopsin (BR) accumulation in archaeon Halobacterium halobium. Experimental results showed that archaeon growth and BR content increased with increasing white light intensity. Green and white LED lights were found to be the most effective for archaeon growth and BR accumulation; here, effectiveness is defined based on photons shined on the bioreactor. The 12-h light/12-h dark cycle illumination pattern resulted in longer lag phase but achieved higher final cell growth and BR accumulation than continuous white light or an instant flash of light/dark illumination. The fade pattern that had smooth transitioning among green, blue, and red lights was better than the jump pattern without transitioning. The highest cell dry weight and BR content of H. halobium were 1.84 g l -1 and 11.76 mg l -1 , respectively, under 29.85 µmol/m 2 s LED white light illumination. The green LED light of 1.39 µmol/m 2 s had the highest energy-specific conversion effectiveness and saved energy consumption by 84 and 87% per cell biomass and BR dry weight, respectively, compared to the worst case of LED white light of 29.85 µmol/m 2 s. Keywords: Archaeon, Bacteriorhodopsin, Halobacterium halobium, Illumination pattern, LED light, Light color.}, number={3}, journal={JOURNAL OF THE ASABE}, author={Lu, Hao and Wang, Jingjing and Yuan, Wenqiao}, year={2024}, pages={525–531} }
 @article{lu_yuan_2018, title={The effect of culture conditions on the accumulation and activity of F0F1 ATP synthase in thermophilic bacteria Bacillus PS3}, volume={93}, ISSN={["1097-4660"]}, DOI={10.1002/jctb.5695}, abstractNote={AbstractBACKGROUNDThe proton‐translocating protein F0F1 ATP synthase is a transmembrane protein that catalyzes ATP synthesis and is important in artificial photosynthesis and other life science studies. The objective of this study was to understand the accumulation and ATPase activity of F0F1 ATP synthase in the thermophilic bacteria Bacillus PS3 affected by culture conditions, including the type of nitrogen source and the concentrations of polypeptone and sodium chloride in the culture medium, as well as medium pH and aeration rate.RESULTSThe highest yield and ATPase activity of purified enzymes were obtained when adding polypeptone as the nitrogen source at higher concentrations. Medium pH and aeration rate showed significant effects on the accumulation and activity of F0F1 ATP synthase. Contrarily, sodium chloride concentration had little effect on the growth of PS3 or F0F1 ATP synthase accumulation. The highest yield and specific activity of purified F0F1 ATP synthase achieved were 1.631 g L−1 and 7.99 µmol min−1 mg−1, under the culture conditions of pH 7, aeration of 3 L min−1 and 0.3% NaCl and 1.2% (w/w) polypeptone concentrations. The F0F1 ATP synthase purified was characterized by SDS‐PAGE and contained all expected subunits.CONCLUSIONAll of the studied culture conditions except for NaCl concentration significantly affected Bacillus PS3 cell growth and ATP synthase accumulation and reactivity. Polypeptone at higher concentrations in the culture medium along with neutral pH and greater aeration rates were desirable. Cell growth and ATPase activity of F0F1 ATP synthase were highly positively associated. © 2018 Society of Chemical Industry}, number={12}, journal={JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY}, author={Lu, Hao and Yuan, Wenqiao}, year={2018}, month={Dec}, pages={3386–3393} }
 @article{lu_yuan_cheng_rose_classen_simmons_2016, title={Modeling the Growth of Archaeon Halobacterium halobium Affected by Temperature and Light}, volume={181}, ISSN={0273-2289 1559-0291}, url={http://dx.doi.org/10.1007/s12010-016-2270-x}, DOI={10.1007/s12010-016-2270-x}, abstractNote={The objective of this study was to develop sigmoidal models, including three-parameter (Quadratic, Logistic, and Gompertz) and four-parameter models (Schnute and Richards) to simulate the growth of archaeon Halobacterium halobium affected by temperature and light. The models were statistically compared by using t test and F test. In the t test, confidence bounds for parameters were used to distinguish among models. For the F test, the lack of fit of the models was compared with the prediction error. The Gompertz model was 100 % accepted by the t test and 97 % accepted by the F test when the temperature effects were considered. Results also indicated that the Gompertz model was 94 % accepted by the F test when the growth of H. halobium was studied under varying light intensities. Thus, the Gompertz model was considered the best among the models studied to describe the growth of H. halobium affected by temperature or light. In addition, the biological growth parameters, including specific growth rate, lag time, and asymptote changes under Gompertz modeling, were evaluated.}, number={3}, journal={Applied Biochemistry and Biotechnology}, publisher={Springer Science and Business Media LLC}, author={Lu, Hao and Yuan, Wenqiao and Cheng, Jay and Rose, Robert B. and Classen, John J. and Simmons, Otto D.}, year={2016}, month={Oct}, pages={1080–1095} }
 @article{ren_lu_zhou_chong_yuan_noh_2017, title={Porous Polydimethylsiloxane as a Gas-Liquid Interface for Microfluidic Applications}, volume={26}, ISSN={["1941-0158"]}, DOI={10.1109/jmems.2016.2618395}, abstractNote={A gas–liquid interface in microfluidic devices requires effective gas absorption and minimal leakage. Here, we present porous polydimethylsiloxane (PDMS) as a gas–liquid interface for microfluidic applications. Two different porous PDMS structures, cube and film, have been prepared and tested for carbon dioxide (CO2) absorption ability in microfluidic devices. Porous PDMS showed higher CO2 absorption rates compared with original PDMS thin films. We also demonstrated the utility of porous PDMS gas–liquid interface via artificial photosynthesis device. The experimental results indicated that the porous PDMS gas–liquid interface facilitates sufficient glucose synthesis by allowing effective CO2 penetration.}, number={1}, journal={JOURNAL OF MICROELECTROMECHANICAL SYSTEMS}, author={Ren, Xiang and Lu, Hao and Zhou, Jack G. and Chong, Parkson Lee-Gau and Yuan, Wenqiao and Noh, Moses}, year={2017}, month={Feb}, pages={120–126} }
 @article{lu_yuan_zhou_chong_2015, title={Glucose Synthesis in a Protein-Based Artificial Photosynthesis System}, volume={177}, ISSN={["1559-0291"]}, DOI={10.1007/s12010-015-1731-y}, abstractNote={The objective of this study was to understand glucose synthesis of a protein-based artificial photosynthesis system affected by operating conditions, including the concentrations of reactants, reaction temperature, and illumination. Results from non-vesicle-based glyceraldehyde-3-phosphate (GAP) and glucose synthesis showed that the initial concentrations of ribulose-1,5-bisphosphate (RuBP) and adenosine triphosphate (ATP), lighting source, and temperature significantly affected glucose synthesis. Higher initial concentrations of RuBP and ATP significantly enhanced GAP synthesis, which was linearly correlated to glucose synthesis, confirming the proper functions of all catalyzing enzymes in the system. White fluorescent light inhibited artificial photosynthesis and reduced glucose synthesis by 79.2 % compared to in the dark. The reaction temperature of 40 °C was optimum, whereas lower or higher temperature reduced glucose synthesis. Glucose synthesis in the vesicle-based artificial photosynthesis system reconstituted with bacteriorhodopsin, F 0 F 1 ATP synthase, and polydimethylsiloxane-methyloxazoline-polydimethylsiloxane triblock copolymer was successfully demonstrated. This system efficiently utilized light-induced ATP to drive glucose synthesis, and 5.2 μg ml−1 glucose was synthesized in 0.78-ml reaction buffer in 7 h. Light-dependent reactions were found to be the bottleneck of the studied artificial photosynthesis system.}, number={1}, journal={APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY}, author={Lu, Hao and Yuan, Wenqiao and Zhou, Jack and Chong, Parkson Lee-Gau}, year={2015}, month={Sep}, pages={105–117} }