The content of this website is exclusively reserved for Healthcare Professionals in countries with applicable health authority product registrations, except those practicing in France as some of the content is not in compliance with the French Advertising law N2011-2012 dated 29th December 2011, article 34.
Cells routinely compartmentalize enzymes for enhanced efficiency of their metabolic pathways. Here we report a general approach to construct DNA nanocaged enzymes for enhancing catalytic activity and stability. Nanocaged enzymes are realized by self-assembly into DNA nanocages with well-controlled stoichiometry and architecture that enabled a systematic study of the impact of both encapsulation and proximal polyanionic surfaces on a set of common metabolic enzymes. Activity assays at both bulk and single-molecule levels demonstrate increased substrate turnover numbers for DNA nanocage-encapsulated enzymes. Unexpectedly, we observe a significant inverse correlation between the size of a protein and its activity enhancement. This effect is consistent with a model wherein distal polyanionic surfaces of the nanocage enhance the stability of active enzyme conformations through the action of a strongly bound hydration layer. We further show that DNA nanocages protect encapsulated enzymes against proteases, demonstrating their practical utility in functional biomaterials and biotechnology.
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How to cite this article: Zhao, Z. et al. Nanocaged enzymes with enhanced catalytic activity and increased stability against protease digestion. Nat. Commun. 7:10619 doi: 10.1038/ncomms10619 (2016).
The National Agricultural Library is one of four national libraries of the United States, with locations in Beltsville, Maryland and Washington, D.C. It houses one of the world's largest and most accessible agricultural information collections and serves as the nexus for a national network of state land-grant and U.S. Department of Agriculture field libraries. In fiscal year 2011 (Oct 2010 through Sept 2011) NAL delivered more than 100 million direct customer service transactions.
On March 18, 2011, as popular revolts swept the Arab world, tensof thousands of demonstrators in Yemen held a protest that they proclaimed theFriday of Dignity. The biggest rally took place at Change Square, a sprawlingprotest camp in the capital, Sanaa. As the protesters finished their middayprayer, dozens of men wearing civilian clothes and armed with military assaultrifles converged on the rally from the south and opened fire.
In September, transitionPresident Hadi ordered the creation of an independent and impartial commissionof inquiry to investigate human rights violations during the 2011 uprising,including the Friday of Dignity attack. The commission is to adhere tointernational standards and recommend measures for accountability andcompensation to victims.
Concerned countries, including the United States and memberstates of the European Union and Gulf Cooperation Council, as well as the UNSecurity Council, should publicly oppose the immunity law, and impose travelbans and asset freezes on any Yemeni officials responsible for the seriousviolations associated with the Friday of Dignity attack and other major crimesduring the 2011 uprising. They should refuse assistance to any security forcesimplicated in these crimes until those responsible are removed from the ranksand held to account.
Concerned governments also should support a resolution atthe Human Rights Council to create an international investigation into theFriday of Dignity attacks and other serious rights violations during the 2011Yemeni uprising should Yemeni efforts fall short.
This report is based on field research conducted by HumanRights Watch in Yemen between February 2011 and November 2012. It examinesviolations of human rights during the so-called Friday of Dignity attack thatkilled at least 45 protesters and wounded some 200 others on March 18, 2011 inSanaa.
Human Rights Watch has confirmed the deaths of 270protesters and bystanders from February through December 2011 in attacks byYemeni security forces and pro-government assailants during anti-Saleh demonstrations.Thousands were injured.[9]
Even as the protests remained overwhelmingly peaceful, armedclashes erupted in May 2011 between government forces and the oppositionfighters of Yemeni elites vying for power. Those clashes rose to the level of anon-international armed conflict in which scores more civilians were killed,many in what appeared to be indiscriminate attacks in violation ofinternational humanitarian law (the laws of war).[10]
Mahweet residents protested his continued tenure and theMahweet governorate council on May 1, 2011 approved a resolution seeking hisremoval because of his alleged role in the killings.[178]At this writing, the governor remained in his post.
During ajailhouse interview with Human Rights Watch, al-Hout, who has been detainedsince July 2011, freely admitted he had been living in a tent in Tahrir Square,the encampment in Sanaa for pro-Saleh protesters. He said he initially had beenjailed for drinking and stabbing a man who tried to steal his money andcellphone.[185]
In September 2012, President Hadi signed a decreeauthorizing the creation of a commission of inquiry to investigate human rightsviolations during the 2011 uprising, including the Friday of Dignity attack,and to recommend accountability measures such as prosecutions of thoseresponsible or compensation to victims. The decree calls for the commission tobe independent and impartial and adhere to international standards, andauthorizes it to hold government officials in contempt for refusing tocooperate with investigations.[215]
[72]Testimony of Walid Hussein Hassanal-Nimri, April 4, 2011, Prosecution InterrogationFile, p. 506. The Prosecution List ofEvidence describes the gunmen as gangs called Khaled Shawter, Saleh al-Maraniand al-Qaa. Prosecution List of Evidence, p. 32.
[105] Committee to Protect Journalists, Journalists Killed: Yemen, Jamal al-Sharaabi, March 18, 2011, -al-sharaabi.php(accessed November 20, 2012). Al-Sharaabi, who wasshot in the face, was a well-known journalist with the opposition newspaperal-Masdar.
[130] Speech by Brig. Gen. Yahya Saleh at a conference broadcasted by Nabanews, March 17, 2011. =wax_fo4OWoU&feature=related. Brigadier General Saleh was at the time of the attack the chief of staff of the CSF and itsde-facto commander. President Hadi appointed a more assertive CSF commander,Major General Fadhl al-Qawsi on May 21, 2012, and removed Gen. Salehfrom the CSF in December 2012.
[194] Testimony, Prosecution Interrogation File, of Abd al-GhaniHamid Ahmad al-Adeeb, p. 93; Fawaz Muhammad Hassanal-Fath, March 22, 2011, p. 199; Haneen Ali MuhammadSaleh Abu Ras, March 22, 2011, p. 201; Alaa Abu BakrHaider Hassan al-Barwi, March19, 2011, p. 163;. The prosecution listed all four as among the 127wounded; see Decision to Dismiss, pp. 3-5. 2ff7e9595c
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