adjective

apo

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Apo (adjective) means describing a protein or molecule that is not currently bound to the partner (like a metal ion or another molecule) it normally works with — its inactive, "empty" form. Example: “The apo form of the enzyme was crystallized before the researchers added its usual cofactor.”

adjective

Describing a protein or molecule that is not currently bound to the partner (like a metal ion or another molecule) it normally works with — its inactive, "empty" form.

"The apo form of the enzyme was crystallized before the researchers added its usual cofactor."

"Comparing the apo and bound structures showed the protein change shape once it grabbed its target."

How to use apo

Learner’s notes

In plain EnglishA biochemistry term meaning "without its usual partner molecule attached" — the bare, unbound version.

When to use it

Technical/scientific term, used mainly in biochemistry and structural biology.

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C2 · Advanced serendipity Fortunate discoveries made entirely by accident.

Gen Z slang rizz Charm — the ability to attract a romantic interest.

B2 · Intermediate empathy The capacity to share another person’s feelings.

C1 · Advanced nonchalant Casually calm and relaxed; unconcerned.

Internet slang delulu Delusional — believing something against the odds.

Etymology nostalgia Greek nostos “return home” + algos “pain”.

C2 · Advanced serendipity Fortunate discoveries made entirely by accident.

Gen Z slang rizz Charm — the ability to attract a romantic interest.

B2 · Intermediate empathy The capacity to share another person’s feelings.

C1 · Advanced nonchalant Casually calm and relaxed; unconcerned.

Internet slang delulu Delusional — believing something against the odds.

Etymology nostalgia Greek nostos “return home” + algos “pain”.

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The _____ form of the enzyme was crystallized before the researchers added its usual cofactor.

Rhymes for apo

capo guapo chapo Gestapo

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Frequently asked questions

What does “apo” mean?

The word “apo” means describing a protein or molecule that is not currently bound to the partner (like a metal ion or another molecule) it normally works with — its inactive, "empty" form. In plain terms, a biochemistry term meaning "without its usual partner molecule attached" — the bare, unbound version.

How do you use “apo” in a sentence?

Here is “apo” used in a sentence: “The apo form of the enzyme was crystallized before the researchers added its usual cofactor.”

What part of speech is “apo”?

“Apo” is an adjective.

What is the meaning of apo?

"apo" (adjective) means describing a protein or molecule that is not currently bound to the partner (like a metal ion or another molecule) it normally works with — its inactive, "empty" form.