下列试剂和酶常用于蛋白质化学的研究中: CNBr异硫氰酸苯酯丹磺酰氯脲6mol/LH

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问题:

下列试剂和酶常用于蛋白质化学的研究中:

CNBr异硫氰酸苯酯丹磺酰氯脲6mol/LHClβ-巯基乙醇水合茚三酮过甲酸胰蛋白酶胰凝乳蛋白酶其中哪一个最适合完成以下各项任务?

(a)测定小肽的氨基酸序列。

(b)鉴定肽的氨基末端残基。

(c)不含二硫键的蛋白质的可逆变性。若有二硫键存在时还需加什么试剂?

(d)在芳香族氨基酸残基羧基侧水解肽键。

(e)在蛋氨酸残基羧基侧水解肽键。

(f)在赖氨酸和精氨酸残基侧水解肽键。

考点:化学工程生物化学生物化学题库
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The famous scientist and thinker, Charles Darwin, was born on February 12, 1809. His family lived not far from the River Severn, England.

Charles’ father was a well-known doctor and the son of a still greater doctor and scientist. Charles’ father hoped that his son would also become a doctor.

As a boy Charles liked to go for walks in the fields and forests. He watched nature and compared what he saw with everything he had read in science books. He also liked collecting very much. He collected many things: eggs, stones, and leaves. His father did not like this, as Charles was not studying very well at school.

为了成为一名医生,十六岁时达尔文就被送到爱丁堡大学(Edinburgh University) 学习。But he was interested in the history of nature.

Then he studied at Cambridge University until 1831.

Some time later, he heard that the ship Beagle was going on a trip to South America and wanted a scientist. His professor advised him to go. He said the trip would be just for Darwin. So when the ship left England in December 1831, Darwin was on it. The research lasted almost five years. The Beagle studied the waters in the sea near South America. It also visited New Zealand, Australia and islands in the Pacific. Darwin saw many new plants and animals. He collected all kinds of plants, which he sent home from the places he visited.

When he returned home, Darwin was warmly greeted by his families and many friends.

In 1842, Darwin went to live in Kent, where he continued his studies of the changes in nature. ②Darwin understood that plants and animals are not always the same, and that they really change.

By 1859, Darwin had finished his famous book The Origin of Species. It made a great hit in the world of science. ③He was opposed (反对) by the church and even by some scientists. But later, more and more scientists agreed with him.

Darwin continued his studies in science until he died in 1882.

请根据文章内容回答问题。

小题1:Why didn’t Charles become a doctor?

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小题2:When did Charles start the research with the Beagle?

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◆根据短文内容,完成下列各题。

小题3:请将①处划线句子翻译成英语。

_______________________________________________________________________

小题4:请将②处划线句子翻译成汉语。

________________________________________________________________________

小题5:请改写③处划线句子, 使其意思与原句一致(每空一词)。

The church and even some scientists ____________ ___________ him.

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依次填入下面一段文字中横线处的关联词语,最恰当的一组是 (  )

小说家应尽可能把人物对话写得流利自然,生动活泼,       不能完全像实际说话。    讲故事或作报告,     又决不能像日常说话那样支离破碎,     不写稿子,    应像一篇文章。

A.虽然而却即使也

B.尽管可是而虽然但

C.尽管而却虽然但

D.虽然相反可即使也

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化学性肺炎最重要的治疗是()

A.应用抗生素

B.维持呼吸

C.应用肾上腺糖皮质激素

D.对症处理

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请简述操作旋转机械设备的注意事项?

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现代经济中货币供给的主体是( )。

A.政府
B.工商企业
C.银行
D.个人

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