Green fluorescent protein (GFP) and its variants /homolog proteins are generally called as GFP-like fluorescent proteins (FPs), which are widely used as visible molecular tools for monitoring a wide range of biologica...Green fluorescent protein (GFP) and its variants /homolog proteins are generally called as GFP-like fluorescent proteins (FPs), which are widely used as visible molecular tools for monitoring a wide range of biological processes due to their capability of simple, accurate and real time quantification. The FPs-based molecular and visible quantification tools are giving more impact on bioprocess engineering, enabling the biomolecule-level dynamic information to be linked with the process-level events. In this review, different applications of FPs in biological engineering with emphasis on rapid molecular bioprocess quantification, such as quantification of the transcription efficiency, the protein production, the protein folding efficiency, the cell concentration, the intracellular microenvironments and so on, would be first introduced. The challenges of using FPs with respect to actual bioprocess applications for the precise quantification including the interaction of FPs and the fused partner proteins, the maturation of FPs, the inner filter effect and sensing technology were then discussed. Finally, the future development for the FPs used in molecular bioprocess quantification would be proposed.展开更多
The aerobic granular sludge was cultivated in a pilot-scale sequencing batch reactor （SBR）, and some of the granules were stored at 8 ℃ for 150 d. Extracellular polymeric substances （EPS） of sludge samples were e...The aerobic granular sludge was cultivated in a pilot-scale sequencing batch reactor （SBR）, and some of the granules were stored at 8 ℃ for 150 d. Extracellular polymeric substances （EPS） of sludge samples were extracted and analyzed during the granulation and storage process. The results show that the contents of protein and EPS increase along with the granulation process, while polysaccharides remain almost unchanged. The content of protein in EPS is almost two-fold larger than that of polysaccharides in granular sludge cultivated with municipal wastewater. Moreover, some of the granules disintegrate during storage, corresponding to the decrease of protein contents in EPS. Three peaks are identified in three-dimensional excitation emission matrix （EEM） fluorescence spectra of the EPS in the aerobic granules. Two peaks （A and B） are attributed to the protein-like fluorophores, and the third （peak C） is related to visible fulvic-like substances. Peak A gradually disappears during storage, while a new peak related to ultraviolet fulvic acid （peak D） is formed. The formation and the stability of aerobic granules are closely dependent on the quantity and composition of EPS proteins. Peak C has no obvious changes during granulation, while the fulvic-like substances present an increase in fluorescence intensities during storage, accompanied with an increase in structural complexity. The fulvie-like substances are also associated with the disintegration of the aerobic granules.展开更多
Specific dynamic action(SDA), the energy expended on all physiological processes that is associated with meal digestion and absorption, is strongly affected by food type. Effects of formulated diet(FMD), macroalgae(AL...Specific dynamic action(SDA), the energy expended on all physiological processes that is associated with meal digestion and absorption, is strongly affected by food type. Effects of formulated diet(FMD), macroalgae(ALG) and sea mud(SMD) diets on the postprandial metabolic response of the green type and the red type of sea cucumber(Apostichopus japonicus) were studied in order to understand their feeding physiology. Food offered to A. japonicus was different in protein, lipid content and energy but not in meal mass. SDA of A. japonicus resulted in a 1.3–2.7 folds of increase in oxygen consumption that can persist for up to 4.8–31.7 h after digesting three different diets. In a given type of sea cucumber, the magnitude of SDA was the highest when fed with FMD, medium with ALG, and the lowest with SMD, which is probably due to the differences in diet components and protein contents. The red type sea cucumber showed greater SDA magnitude than the green type with each diet treatment, which might result from the difference in factorial scope between the two types of sea cucumber. However, the smallest magnitude or even no difference was observed between the two types of A. japonicus in SMD group, perhaps owing to the poor nutrition and digestion of sea mud.展开更多
The mixing of protein solutions with that of precipitating agents is very important in protein crystallization experiments. In this work, the interferometry images were recorded during the mixing of two proteins with ...The mixing of protein solutions with that of precipitating agents is very important in protein crystallization experiments. In this work, the interferometry images were recorded during the mixing of two proteins with different molecular weights： lysozyme of -14.6 kDa, trypsin of -23.3 kDa and pepsin of -34.8 kDa were placed in a Mach-Zehnder interferometer. The protein mo- lecular weight dependence on the competition of the transport process and kinetics at the interface was studied. The concentra- tion profiles of protein solutions were calculated to analyze the mass transfer during the mixing process. It was observed that the mass transfer process is more efficient during the mixing of proteins with higher molecular weights. In addition, the more rapid concentration changes above the interface suggest that convection may dominate the diffusion. The phenomenon of con- vection is higher in the protein solutions with higher molecular weight.展开更多
基金Supported by the National Natural Science Foundation of China （20836004 20806046） the Special Fund for Major State Basic Research Program of China （2009CB724702） the National High Technology Research and Development Program ofChina （2009AA062903）
文摘Green fluorescent protein (GFP) and its variants /homolog proteins are generally called as GFP-like fluorescent proteins (FPs), which are widely used as visible molecular tools for monitoring a wide range of biological processes due to their capability of simple, accurate and real time quantification. The FPs-based molecular and visible quantification tools are giving more impact on bioprocess engineering, enabling the biomolecule-level dynamic information to be linked with the process-level events. In this review, different applications of FPs in biological engineering with emphasis on rapid molecular bioprocess quantification, such as quantification of the transcription efficiency, the protein production, the protein folding efficiency, the cell concentration, the intracellular microenvironments and so on, would be first introduced. The challenges of using FPs with respect to actual bioprocess applications for the precise quantification including the interaction of FPs and the fused partner proteins, the maturation of FPs, the inner filter effect and sensing technology were then discussed. Finally, the future development for the FPs used in molecular bioprocess quantification would be proposed.
基金Project(2006AA06Z318) supported by the National High-Tech Research and Development Program of China
文摘The aerobic granular sludge was cultivated in a pilot-scale sequencing batch reactor （SBR）, and some of the granules were stored at 8 ℃ for 150 d. Extracellular polymeric substances （EPS） of sludge samples were extracted and analyzed during the granulation and storage process. The results show that the contents of protein and EPS increase along with the granulation process, while polysaccharides remain almost unchanged. The content of protein in EPS is almost two-fold larger than that of polysaccharides in granular sludge cultivated with municipal wastewater. Moreover, some of the granules disintegrate during storage, corresponding to the decrease of protein contents in EPS. Three peaks are identified in three-dimensional excitation emission matrix （EEM） fluorescence spectra of the EPS in the aerobic granules. Two peaks （A and B） are attributed to the protein-like fluorophores, and the third （peak C） is related to visible fulvic-like substances. Peak A gradually disappears during storage, while a new peak related to ultraviolet fulvic acid （peak D） is formed. The formation and the stability of aerobic granules are closely dependent on the quantity and composition of EPS proteins. Peak C has no obvious changes during granulation, while the fulvic-like substances present an increase in fluorescence intensities during storage, accompanied with an increase in structural complexity. The fulvie-like substances are also associated with the disintegration of the aerobic granules.
基金the National Key Technologies Research and Development Program of China (No. 2011BAD13B03)Foundation of Liaoning Educational Committee (No. L2014254)
文摘Specific dynamic action(SDA), the energy expended on all physiological processes that is associated with meal digestion and absorption, is strongly affected by food type. Effects of formulated diet(FMD), macroalgae(ALG) and sea mud(SMD) diets on the postprandial metabolic response of the green type and the red type of sea cucumber(Apostichopus japonicus) were studied in order to understand their feeding physiology. Food offered to A. japonicus was different in protein, lipid content and energy but not in meal mass. SDA of A. japonicus resulted in a 1.3–2.7 folds of increase in oxygen consumption that can persist for up to 4.8–31.7 h after digesting three different diets. In a given type of sea cucumber, the magnitude of SDA was the highest when fed with FMD, medium with ALG, and the lowest with SMD, which is probably due to the differences in diet components and protein contents. The red type sea cucumber showed greater SDA magnitude than the green type with each diet treatment, which might result from the difference in factorial scope between the two types of sea cucumber. However, the smallest magnitude or even no difference was observed between the two types of A. japonicus in SMD group, perhaps owing to the poor nutrition and digestion of sea mud.
基金supported by the National Natural Science Foundation of China (Grant No. 51076128)the Doctoral Fund of Ministry of Education of China (Grant No. 2009021110008)
文摘The mixing of protein solutions with that of precipitating agents is very important in protein crystallization experiments. In this work, the interferometry images were recorded during the mixing of two proteins with different molecular weights： lysozyme of -14.6 kDa, trypsin of -23.3 kDa and pepsin of -34.8 kDa were placed in a Mach-Zehnder interferometer. The protein mo- lecular weight dependence on the competition of the transport process and kinetics at the interface was studied. The concentra- tion profiles of protein solutions were calculated to analyze the mass transfer during the mixing process. It was observed that the mass transfer process is more efficient during the mixing of proteins with higher molecular weights. In addition, the more rapid concentration changes above the interface suggest that convection may dominate the diffusion. The phenomenon of con- vection is higher in the protein solutions with higher molecular weight.
