Tyrosine residues initiated photopolymerization in living organisms.

Towards intracellular engineering of living organisms, the development of new biocompatible polymerization system applicable for an intrinsically non-natural macromolecules synthesis for modulating living organism function/behavior is a key step. Herein, we find that the tyrosine residues in the cofactor-free proteins can be employed to mediate controlled radical polymerization under 405 nm light. A proton-coupled electron transfer (PCET) mechanism between the excited-state TyrOH* residue in proteins and the monomer or the chain transfer agent is confirmed. By using Tyr-containing proteins, a wide range of well-defined polymers are successfully generated. Especially, the developed photopolymerization system shows good biocompatibility, which can achieve in-situ extracellular polymerization from the surface of yeast cells for agglutination/anti-agglutination functional manipulation or intracellular polymerization inside yeast cells, respectively. Besides providing a universal aqueous photopolymerization system, this study should contribute a new way to generate various non-natural polymers in vitro or in vivo to engineer living organism functions and behaviours.

Algal cell bionics as a step towards photosynthesis-independent hydrogen production.

The engineering and modulation of living micro-organisms is a key challenge in green bio-manufacturing for the development of sustainable and carbon-neutral energy technologies. Here, we develop a cellular bionic approach in which living algal cells are interfaced with an ultra-thin shell of a conductive polymer along with a calcium carbonate exoskeleton to produce a discrete cellular micro-niche capable of sustained photosynthetic and photosynthetic-independent hydrogen production. The surface-augmented algal cells induce oxygen depletion, conduct photo-induced extracellular electrons, and provide structural and chemical stability that collectively give rise to localized hypoxic conditions and concomitant hydrogenase activity under daylight in air. We show that assembly of the living cellular micro-niche opens a direct extracellular photoelectron pathway to hydrogenase resulting in photosynthesis-independent hydrogen evolution for 200 d. In addition, surface-conductive dead algal cells continue to produce hydrogen for up to 8 d due to their structural stability and retention of functional hydrogenases. Overall, the integration of artificial biological hydrogen production pathways and natural photosynthesis in surface-augmented algal cells provides a cellular bionic approach to enhanced green hydrogen production under environmentally benign conditions and could pave the way to new opportunities in sustainable energy production.

Biotic communities inspired proteinosome-based aggregation for enhancing utilization rate of enzyme.

Compared with the individuals, the collective behavior of biotic communities could show certain superior characteristics. Inspired by this idea and based on the conjugation between phenylboronic acid-grafted mesoporous silica nanoparticles and the polysaccharide functionalized membrane of proteinosomes, a type of proteinosomes-based aggregations was constructed. We demonstrated the emergent characteristics of proteinosomes aggregations including accelerated settling velocity and population surviving by sacrificing outside members for the inside. Moreover, this kind of "hand in hand" architecture provided the proteinosomes aggregations with the characteristic of resistance to the negative pressure phagocytosis of micropipette, as well as enhancing utilization rate of the encapsulated enzymes. Overall, it is anticipated that the construction and application of proteinosomes aggregations could contribute to advance the functionality of life-like assembled biomaterial in another way.

Construction of coacervates in proteinosome hybrid microcompartments with enhanced cascade enzymatic reactions.

A spatially segregative coacervate-in-proteinosome hybrid microcompartment is constructed by co-encapsulation of either positively or negatively charged polyelectrolytes within proteinosomes with enhanced cascade enzymatic reactions, providing a step towards the development of artificial eukaryotic cell like microcompartments.

Image Risk Assessment of the Thyroid Cancer Model Based on Discriminant Analysis and the Value of TAP and CEA Combined Detection.

The incidence rate of thyroid disease is increasing rapidly worldwide, and the number of thyroid patients is increasing. In this study, serum TAP (tumor abnormal protein) and CEA (carcinoembryonic antigen) were used to detect patients with thyroid nodules of class IV and above to explore the value of serum TAP combined detection of CEA in the risk assessment of thyroid cancer. In this paper, 400 patients with thyroid nodules above class IV diagnosed by physical examination in our hospital health management center from January 2019 to June 2021 were included in the study. Combined with the pathological test results, the patients were divided into risk groups. At the same time, different groups of serum TAP and CEA levels were detected by aggregation and electrochemiluminescence methods, and serum TAP and CEA levels were analyzed according to the pathological diagnostic indicators of CEA levels. The results showed that the levels of serum TAP and CEA in patients with thyroid cancer were significantly higher than those in patients with benign thyroid diseases, and the difference was statistically significant (P < 0.05). The sensitivity, specificity, and AUC under the ROC curve area of serum TAP were 85.25%, 85.06%, and 0.605, respectively. The sensitivity, specificity, and AUC under the ROC curve area of serum CEA were 89.85%, 88.00%, and 0.627, respectively. The sensitivity, specificity, and AUC under the ROC curve area of serum TAP combined with CEA were 96.84%, 96.79%, and 0.915, respectively. Therefore, the combined detection of serum TAP and CEA has a high early screening value in thyroid cancer.

Membranization of Coacervates into Artificial Phagocytes with Predation toward Bacteria.

Coacervate-based membraneless organelles with diverse functionality as well as the capability of mimicking intracellular physiological environments are attracting researchers' great interest. However, the further studies focusing on functionalized membranization of coacervate as a step toward an advanced membrane-bound protocell are still rare. In this study, we develop a way to compartmentalize coacervate based on reconstitution with a natural cellular wall, which could then serve as a promising chassis for the development of protocells with selective sequestration of various biomacromolecules. Significantly, the compartmentalized protocell could behave like a phagocyte and selectively capture, engulf, and then kill Escherichia coli efficiently. Taken together, our studies present a strategy for advancing coacervate-based protocell design as well as the development of smart materials with on-demand functionalization.

Construction of Hybrid Bi-microcompartments with Exocytosis-Inspired Behavior toward Fast Temperature-Modulated Transportation of Living Organisms.

Inspired by the unique characteristics of living cells, the creation of life-inspired functional ensembles is a rapidly expanding research topic, enabling transformative applications in various disciplines. Herein, we report a facile method for the fabrication of phospholipid and block copolymer hybrid bi-microcompartments via spontaneous asymmetric assembly at the water/tributyrin interface, whereby the temperature-mediated dewetting of the inner microcompartments allowed for exocytosis to occur in the constructed system. The exocytosis location and commencement time could be controlled by the buoyancy of the inner microcompartment and temperature, respectively. Furthermore, the constructed bi-microcompartments showed excellent biocompatibility and a universal loading capacity toward cargoes of widely ranging sizes; thus, the proliferation and temperature-programmed transportation of living organisms was achieved. Our results highlight opportunities for the development of complex mesoscale dynamic ensembles with life-inspired behaviors and provide a novel platform for on-demand transport of various living organisms.

Photosynthetic hydrogen production by droplet-based microbial micro-reactors under aerobic conditions.

The spontaneous self-assembly of multicellular ensembles into living materials with synergistic structure and function remains a considerable challenge in biotechnology and synthetic biology. Here, we exploit the aqueous two-phase separation of dextran-in-PEG emulsion micro-droplets for the capture, spatial organization and immobilization of algal cells or algal/bacterial cell communities to produce discrete multicellular spheroids capable of both aerobic (oxygen producing) and hypoxic (hydrogen producing) photosynthesis in daylight under air. We show that localized oxygen depletion results in hydrogen production from the core of the algal microscale reactor, and demonstrate that enhanced levels of hydrogen evolution can be achieved synergistically by spontaneously enclosing the photosynthetic cells within a shell of bacterial cells undergoing aerobic respiration. Our results highlight a promising droplet-based environmentally benign approach to dispersible photosynthetic microbial micro-reactors comprising segregated cellular micro-niches with dual functionality, and provide a step towards photobiological hydrogen production under aerobic conditions.

Near-Infrared-Induced Contractile Proteinosome Microreactor with a Fast Control on Enzymatic Reactions.

Inspired by the compartmentalized structure of cells, self-regulating responsive hollow microcapsules are highly desirable for the modulation of enzymatic reactions. Here, we report a strategy to fabricate gold nanorod embedded proteinosomes by covalently grafting gold nanorods onto the surface of proteinosomes. The excellent photothermal conversion efficiency of the embedded gold nanorod and the thermal phase transition of the grafted PNIPAAm allow the constructed hybrid proteinosomes to show reversible contraction behaviors triggered by near-infrared light with the molecular weight cutoff of the membrane decreased to ca. 50 kDa, and importantly, the contraction frequency of the constructed proteinosomes could be as fast as 1 min and last for at least 15 cycles. Subsequently, the effective encapsulation of three cascade enzymes into the proteinosomes realizes the construction of a near-infrared responsive microreactor that allows control of the cascade reaction by near-infrared illumination, thereby enabling reversible on and off of the enzymatic reaction. Such microcapsule-based reactors demonstrate the potential to alter the membrane molecular weight cutoff, and it is believed that the development of such responsive microcapsules will have great potential for studying cellular responses and provide a platform for future applications in biosensing and drug delivery.

An Unexpected Oxidosqualene Cyclase Active Site Architecture in the Iris tectorum Multifunctional α-Amyrin Synthase.

Ordered polycyclization catalyzed by oxidosqualene synthases (OSCs) morph a common linear precursor into structurally complex and diverse triterpene scaffolds with varied bioactivities. We identified three OSCs from Iris tectorum. ItOSC2 is a rare multifunctional α-amyrin synthase. Sequence comparisons, site-directed mutagenesis and multiscale simulations revealed that three spatially clustered residues, Y531/L256/L258 form an unusual Y-LL triad at the active site, replacing the highly conserved W-xY triad occurring in other amyrin synthases. The discovery of this unprecedented active site architecture in ItOSC2 underscores the plasticity of terpene cyclase catalytic mechanisms and opens new avenues for protein engineering towards custom designed OSCs.

Interfacial self-assembly of gold nanoparticle-polymer nanoconjugates into microcapsules with near-infrared light modulated biphasic catalysis efficiency.

A high throughput way to generate gold nanoparticle-based microcapsules was demonstrated based on the interfacial assembly in a water and 2-ethyl-1-hexanol two phase system. The obtained gold microcapsules exhibit superior stability, good flexibility, ductility, and a significant enhancement (about 10-fold) in the biphasic catalytic reaction rate upon near-infrared light irradiation.

[Study on the influencing factor of cultivating mungbean sprouts rich in chromium].

Getting organic chromium by cultivating chromium-enriched mungbean sprouts was studied. Chromium content in mung-bean sprouts was determined and the growth performance was observed under different conditions. The result showed that the optimal condition of cultivating chromium-enriched mungbean sprouts was soaking mungbean seeds in 40 mg/kg chromium solution about 24 hours, then cultivating under 25 degrees C for 5 days. The supernatant of chromium-enriched mungbean sprouts and normal mungbean sprouts were tested by scanning with ultraviolet spectrometry within the range of 200-320 nm wavelength. It is found that a characteristic ultraviolet absorption peak appears at 257 nm, and its optical density is descended with the increasing of chromium in the chromium-enriched mung-bean sprouts.