生物制造 经典文献导读|2017年12月05日

ArtificialMultienzyme Supramolecular Device: Highly Ordered Self Assembly of OligomericEnzymes In Vitro and In Vivo

一种人工多酶超分子组装体：体内与体外的高度有序化自组装酶体系

Xin Gao, Shuai Yang,Chengcheng Zhao, Yuhong Ren,* and Dongzhi Wei*

Angew. Chem. Int. Ed.2014, 53, 1-5 http://dx.doi.org/10.1002/anie.201405016

Abstract

A strategy forscaffold-free self-assembly of multiple oligomeric enzymes was developed byexploiting enzyme oligomerization and protein–protein interaction properties, andwas tested both in vitro and in vivo. Octameric leucine dehydrogenase anddimeric formate dehydrogenase were fused to a PDZ (PSD95/Dlg1/zo-1) domain andits ligand, respectively. The fusion proteins self-assembled into extended supramolecularinteraction networks. Scanning-electron and atomic-force microscopy showed thatthe assemblies assumed two-dimensional layer-like structures. A fluorescencecomplementation assay indicated that the assemblies were localized to the polesof cells. Moreover, both in vitro and in vivo assemblies showed higher NAD(H)recycling efficiency and structural stability than did unassembled structureswhen applied to a coenzyme recycling system. This work provides a novel methodfor developing artificial multienzyme supramolecular devices and forcompartmentalizing metabolic enzyme cascades in living cells by supramolecularmagnetic precipitation is highly selective and efficient.

（导读：郭钟伟）本文提供了一种体内、体外无支架多酶组装策略：利用酶的寡聚化现象以及蛋白质与蛋白质相互作用的性质实现组装。具体来说：作为八聚体的亮氨酸脱氢酶、二聚体的甲酸脱氢酶、基因工程融合在酶结构上的PDZ linker作为构建单元。整个蛋白复合体自发组装成超分子相互作用体系，发挥更高层次的催化作用。SEM与AFM结果证明了组装体的二维层状结构。通过荧光互补试验证明了两种酶的体内组装发生在细胞两极中。无论体内组装还是体外组装，整个辅酶循环的效率都比未组装体系得到了提高。

A microfluidic platform for the high-throughput study of pathological cardiachypertrophy

一个用于研究病理性心脏肥大的微流控芯片

Hesam Parsa,Bryan Z. Wang  and Gordana Vunjak-Novakovic. Lab Chip, 2017, 17, 3264.

http://pubs.rsc.org/en/content/articlelanding/2017/lc/c7lc00415j#!div

Abstract

Current in vitro models fall short in deciphering themechanisms of cardiac hypertrophy induced by volume overload. We developed apneumatic microfluidic platform for high-throughput studies of cardiachypertrophy that enables repetitive (hundreds of thousands of times) and robust(over several weeks) manipulation of cardiac μtissues. The platform is reusablefor stable and reproducible mechanical stimulation of cardiac μtissues (eachcontaining only 5000 cells). Heterotypic and homotypic μtissues produced in thedevice were pneumatically loaded in a range of regimes, with real-time on-chipanalysis of tissue phenotypes. Concentrated loading of the three-dimensionalcardiac tissue faithfully recapitulated the pathology of volume overload seenin native heart tissue. Sustained volume overload of μtissues was sufficient toinduce pathological cardiac remodeling associated with upregulation of thefetal gene program, in a dosedependent manner.

（导读：夏圣悦）病理性心脏肥大导致的心脏衰竭是许多心脏病患者导致死亡的重要原因，目前还无法清楚地得知病理性心脏肥大产生的具体原因，本文介绍了一种可以大批量制作并准确进行单个测量的微流控芯片，使用气动模拟心脏振动，多频次振动模拟病理性心脏肥大产生过程，用于研究病理性心脏肥大产生的具体原因。同时，在我看来，本文中微流控芯片的制作过程以及每个芯片使用极少数细胞进行研究的方法都是值得借鉴的方面。