The development of effective antifreeze peptides to control ice growth has attracted a significant amount of attention yet still remains a great challenge.Here,we propose a novel design method based on in-depth invest...The development of effective antifreeze peptides to control ice growth has attracted a significant amount of attention yet still remains a great challenge.Here,we propose a novel design method based on in-depth investigation of repetitive motifs in various ice-binding proteins(IBPs)with evolution analysis.In this way,several peptides with notable antifreeze activity were developed.In particular,a designed antifreeze peptide named AVD exhibits ideal ice recrystallization inhibition(IRI),solubility,and biocompatibility,making it suitable for use as a cryoprotective agent(CPA).A mutation analysis and molecular dynamics(MD)simulations indicated that the Thr6 and Asn8 residues of the AVD peptide are fundamental to its ice-binding capacity,while the Ser18 residue can synergistically enhance their interaction with ice,revealing the antifreeze mechanism of AVD.Furthermore,to evaluate the cryoprotection potential of AVD,the peptide was successfully employed for the cryopreservation of various cells,which demonstrated significant post-freezing cell recovery.This work opens up a new avenue for designing antifreeze materials and provides peptide-based functional modules for synthetic biology.展开更多
It is known that the tribological behaviors of snake skins are contributed by the synergistic action of multiple factors, such as surface morphology and mechanical properties, which has inspired fabrication of scale-l...It is known that the tribological behaviors of snake skins are contributed by the synergistic action of multiple factors, such as surface morphology and mechanical properties, which has inspired fabrication of scale-like surface textures in recent years. However, the coupling effect and mechanism remain to be elucidated. In this work, the morphology and mechanical properties of the scales from different body sections （leading body half, middle trunk and tailing body half） and positions （dorsal, lateral and ventral） of Boa constrictor and Eryx tataricus were characterized and compared to investigate the corresponding effects on the tribological behaviors and to probe the possible coupling mechanism. The morphological characterizations of scanning electron microscopy and atomic force microscopy revealed sig- nificant differences between the two species that the scales from Boa constrictor are rougher in general. The mechanical properties measured by nanoindentation corroboratively demonstrated substantial differences in elastic modulus and hardness. Interestingly, the ventral scales with lower surface roughness, together with relatively larger elastic modulus and hardness, manifest higher friction coefficients. A ＂double-crossed＂ hypothesis was proposed to explain the observed coupling effect of morphology and mechanical properties on friction, which may afford valuable insights for the design of bionic surface with desirable tribological performance.展开更多
基金supported by the National Key Research and Development Program of China (2021YFC2100800)the National Natural Science Foundation of China (22078238,21961132005,and 21908160)+1 种基金the Open Funding Project of the National Key Laboratory of Biochemical Engineeringthe Program of Introducing Talents of Discipline to Universities (BP0618007)。
文摘The development of effective antifreeze peptides to control ice growth has attracted a significant amount of attention yet still remains a great challenge.Here,we propose a novel design method based on in-depth investigation of repetitive motifs in various ice-binding proteins(IBPs)with evolution analysis.In this way,several peptides with notable antifreeze activity were developed.In particular,a designed antifreeze peptide named AVD exhibits ideal ice recrystallization inhibition(IRI),solubility,and biocompatibility,making it suitable for use as a cryoprotective agent(CPA).A mutation analysis and molecular dynamics(MD)simulations indicated that the Thr6 and Asn8 residues of the AVD peptide are fundamental to its ice-binding capacity,while the Ser18 residue can synergistically enhance their interaction with ice,revealing the antifreeze mechanism of AVD.Furthermore,to evaluate the cryoprotection potential of AVD,the peptide was successfully employed for the cryopreservation of various cells,which demonstrated significant post-freezing cell recovery.This work opens up a new avenue for designing antifreeze materials and provides peptide-based functional modules for synthetic biology.
基金This work was supported by National Natural Science Foundation of China （51375204 and U1601203）, Jilin Provincial Science ＆ Technology Department （20140101056JC）, and Province Joint Fund （SXGJSF2017-2-4 and SXGJQY2017-1） and JLUSTIRT Program of Jilin University.
文摘It is known that the tribological behaviors of snake skins are contributed by the synergistic action of multiple factors, such as surface morphology and mechanical properties, which has inspired fabrication of scale-like surface textures in recent years. However, the coupling effect and mechanism remain to be elucidated. In this work, the morphology and mechanical properties of the scales from different body sections （leading body half, middle trunk and tailing body half） and positions （dorsal, lateral and ventral） of Boa constrictor and Eryx tataricus were characterized and compared to investigate the corresponding effects on the tribological behaviors and to probe the possible coupling mechanism. The morphological characterizations of scanning electron microscopy and atomic force microscopy revealed sig- nificant differences between the two species that the scales from Boa constrictor are rougher in general. The mechanical properties measured by nanoindentation corroboratively demonstrated substantial differences in elastic modulus and hardness. Interestingly, the ventral scales with lower surface roughness, together with relatively larger elastic modulus and hardness, manifest higher friction coefficients. A ＂double-crossed＂ hypothesis was proposed to explain the observed coupling effect of morphology and mechanical properties on friction, which may afford valuable insights for the design of bionic surface with desirable tribological performance.
