VOA标准英语2012--Scientists Provide Template for Developing New Anti-malarial Drug

Scientists Provide Template for Developing New Anti-malarial Drug

A team of scientists at Washington University in St. Louis, Missouri, spent six years trying to understand the structure and function of a protein essential to the survival of Plasmodium falciparum. That's the single-celled protozoan that lives inside mosquitos and is responsible for the most lethal² form of malaria¹. The microscopic³ parasite⁴ needs the protein, an enzyme⁵ called PMT, to make its cell membranes⁶, and it cannot survive without it.
Dr. Joseph Jez, who led the research team, says cracking the code of PMT's design is like finding malaria's fatal weakness:
"If you can target the protein and basically kill the activity of the protein, you shut down the production of building blocks for membranes which will then make the organism die off, or slow down the progression," said Jez.
Jez and his colleagues used a complex and painstaking⁷ method called protein crystallization to view PMT's molecular⁸ structure in three dimensions. He says the method was critical to their study.
"If you can understand what the molecules⁹ look like in three dimensions, you can start to design or develop pharmaceuticals¹⁰ that target it specifically," Jez noted¹¹. "The uniqueness of it is that this is a new potential anti-parasitic¹² target for Plasmodium and also in terms of nematodes or worms, which are parasites¹³ as well."
Jez adds that because Plasmodium PMT is NOT found in human cells, any drug that targets the protein could be safely administered to humans.
Dr. Neeraj Mistry is managing director of the Global Network for Neglected Tropical Diseases. He says the research is an important step toward powerful and safe new drugs to fight the worldwide malaria plague:
"It opens the door to developing new drugs that specifically affect the parasite - will not affect the host - that will not have severe side effects - will only affect the parasite," Mistry noted. "Which means that upon identification of that pathway, we might be able to come up with a unique drug that actually affects that malaria parasite."
The work of identifying compounds that target the Plasmodium PMT is just beginning. But the Washington University research provides new hope not only for new anti-malarial drugs, but for compounds that can destroy a variety of disease-causing parasitic worms as well as weedy plants that all depend on the same PMT protein.

1 malaria   

n.疟疾

参考例句：

• He had frequent attacks of malaria.他常患疟疾。
• Malaria is a kind of serious malady.疟疾是一种严重的疾病。

2 lethal   

adj.致死的；毁灭性的

参考例句：

• A hammer can be a lethal weapon.铁锤可以是致命的武器。
• She took a lethal amount of poison and died.她服了致命剂量的毒药死了。

3 microscopic   

adj.微小的，细微的，极小的，显微的

参考例句：

• It's impossible to read his microscopic handwriting.不可能看清他那极小的书写字迹。
• A plant's lungs are the microscopic pores in its leaves.植物的肺就是其叶片上微细的气孔。

4 parasite   

n.寄生虫；寄生菌；食客

参考例句：

• The lazy man was a parasite on his family.那懒汉是家里的寄生虫。
• I don't want to be a parasite.I must earn my own way in life.我不想做寄生虫，我要自己养活自己。

5 enzyme   

n.酵素，酶

参考例句：

• Above a certain temperature,the enzyme molecule will become unfolded.超过一定温度，酶分子将会展开。
• An enzyme that dissolves the fibrin of blood clots.能溶解血凝块中的纤维的酶。

6 membranes   

n.（动物或植物体内的）薄膜( membrane的名词复数 )；隔膜；（可起防水、防风等作用的）膜状物

参考例句：

• The waste material is placed in cells with permeable membranes. 废液置于有渗透膜的槽中。 来自辞典例句
• The sarcoplasmic reticulum is a system of intracellular membranes. 肌浆网属于细胞内膜系统。 来自辞典例句

7 painstaking   

adj.苦干的；艰苦的，费力的，刻苦的

参考例句：

• She is not very clever but she is painstaking.她并不很聪明，但肯下苦功夫。
• Through years of our painstaking efforts,we have at last achieved what we have today.大家经过多少年的努力，才取得今天的成绩。

8 molecular   

adj.分子的；克分子的

参考例句：

• The research will provide direct insight into molecular mechanisms.这项研究将使人能够直接地了解分子的机理。
• For the pressure to become zero, molecular bombardment must cease.当压强趋近于零时，分子的碰撞就停止了。

9 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

10 pharmaceuticals   

n.医药品；药物( pharmaceutical的名词复数 )

参考例句：

• the development of new pharmaceuticals 新药的开发
• The companies are pouring trillions of yen into biotechnology research,especially for pharmaceuticals and new seeds. 这些公司将大量资金投入生物工艺学研究，尤其是药品和新种子方面。 来自《简明英汉词典》

11 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。

12 parasitic   

adj.寄生的

参考例句：

• Will global warming mean the spread of tropical parasitic diseases?全球变暖是否意味着热带寄生虫病会蔓延呢？
• By definition,this way of life is parasitic.从其含义来说，这是种寄生虫的生活方式。

13 parasites   

寄生物( parasite的名词复数 )； 靠他人为生的人； 诸虫

参考例句：

• These symptoms may be referable to virus infection rather than parasites. 这些症状也许是由病毒感染引起的，而与寄生虫无关。
• Kangaroos harbor a vast range of parasites. 袋鼠身上有各种各样的寄生虫。