Scientists at The Scripps Research Institute have discovered a class of compounds that block the SARS virus from replicating, a finding that may open the door to new drug targets against the deadly disease. The study was conducted by researchers from Scripps Research; the GenomicsResearchCenter, Academia Sinica, Taiwan; and the NationalTaiwanUniversity. It is being published today in the journal Chemistry and Biology.
Chi-Huey Wong is currently the Ernest W. Hahn Chair in Chemistry at the Skaggs Institute of Chemical Biology and directs the Scripps Research lab heading the study. He said the new finding is an important step in developing a possible drug treatment against SARS.
"We have been working on the problem of SARS since the epidemic started in 2003," Wong said. "This new class of inhibitors represents the most potent SARS virus protease inhibitors known today."
The path to todays research finding has taken several years. In 2002, Severe Acute Respiratory Syndrome (SARS) emerged in rural China and eventually spread to 32 countries, according to the World Health Organization. SARS is caused by a ring-shaped virus, known as a coronavirus. The SARS coronavirus is suspected of originating in animal populations before migrating to humans. Hardest-hit were six Asian nations. By the time the epidemic had been controlled in 2003, the disease infected more than 8,000 people, causing 800 deaths. There is no current effective treatment or vaccine.
Researchers have known since 2003 that a site on the virus is responsible for mediating proteases that allow the virus to replicate. Since then researchers have been testing protease inhibitors to lock up this site, known as SARS 3CLpro, and effectively stop the virus from infecting additional cells in the body.
In 2004, Wongs lab discovered that Lopinavir, a protease inhibitor of HIV also known as TL3, also served as weak inhibitor of the SARS 3CLpro site (PNAS, 101, 10012-10017). Since then, members of Wongs group further studied Lopinavir and are preparing it for clinical trials against SARS.
Researchers in Wongs lab at Scripps Research and in Taiwan have been looking at other Liponavir-related compounds for similar blocking effects. During these experiments, they found that a group of catalyzing agents used to help promote chemical reactions in the laboratory were actually more powerful in blocking the SARS protease than either the Lopinavir or any of the target compounds.
These organic compounds are called benzotriazole esters. The esters entered the SARS protease site, formed an intermediary compound, then inactivated the SARS enzyme. The findings were confirmed using mass spectrometry analysis of the enzyme intermediary.
"These benzotriazole esters are relatively stable and act as suicide inhibitors," Wong said. "They block the enzyme, are transformed through a co-valent bond, and are unable to get out."
Wong said the findings published today provide better insight into the mode of action of the enzyme, which may lead to development of a drug against SARS. The findings were made by using rapid drug discovery techniques developed in the Wong lab to screen large numbers of weak enzyme inhibitors, and then attaching additional compounds to look for stronger reactions.
Research associate Chung-Yi Wu, a member of the Wong lab, is the papers lead author. He said the finding was unexpected. "We wanted to improve Liponavir activity," Wu said. "But we found this very surprising and serendipitous result."
Other authors of the study include Ke-Yung King, Chih-Jun Kuo, Jim-Min Fang, Ying-Ta Wu, Ming-Yi Ho, Chung-Lin Liao, Jiun-Jie Shie and Po-Huang Liang of the GenomcsResearchCenter, Academia Sinica, Taiwan and NationalTaiwanUniversity, Taipei, Taiwan. The study was supported by the National Science Council, Taiwan, and GenomicsResearchCenter, Academia Sinica. The work is supported by the National Science Council, Taiwan and GenomicsResearchCenter, Academia Sinica.
Source: Scripps Research Institute
Â
Â
Â
Ensuring Safety and Comfort: The Urgent Need for Well-Fitted PPE in Health Care
April 5th 2024Personal protective equipment (PPE) stands as the first line of defense against infectious diseases in health care. Yet, the issue of ill-fitting PPE, especially for women, remains a significant challenge.
COVID-19 Harmonization: Balancing Risks and Benefits of CDC's Latest Move
March 11th 2024The CDC's recent decision to align recommendations for respiratory viruses, particularly COVID-19, has garnered support from the public and infectious disease societies. However, as the Infectious Diseases Society of America (IDSA) lends its backing to the CDC's harmonization efforts, concerns persist regarding the implications of this shift, especially considering the Omicron variant's unique characteristics and the ongoing challenges posed by COVID-19's multi-system impacts.
Voices of Resilience: Q&A With the Editor of "Corona City: Voices From an Epicenter"
March 1st 2024Step into the diverse and poignant world of "Corona City: Voices From an Epicenter" with editor Lorraine Ash, MA. In this insightful Q&A, learn about the origins of this remarkable anthology, the challenges faced in capturing raw, unfiltered narratives of the COVID-19 pandemic, and the lasting impact of these stories on readers and communities alike.
Rare Disease Day 2024: Spotlight on Rare Infectious Diseases
February 29th 2024Rare Disease Day on February 29, 2024, shines a global light on the impact of rare diseases, including rare infectious diseases. With a focus on early diagnosis and treatment access, this day highlights the struggles of those with rare conditions.