engineering

L-cysteate sulfo-lyase

L-cysteate sulfo-lyase is a engineering topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand L-cysteate sulfo-lyase rather than just read about it. In short: The enzyme L-cysteate sulfo-lyase (EC 4.4.1.25) catalyzes the reaction L-cysteate + H2O = hydrogensulfite + pyruvate + NH3 (overall reaction) (1a) L-cysteate = hydrogensulfite + 2-aminoprop-2-enoate (1b) 2-aminoprop-2-enoate = 2-iminopropanoate (spontaneous) (1c) 2-iminopropanoate + H2O = pyruvate + NH3 (spontaneous) This enzyme belongs to the family of lyases, specifically the class of carbon-sulfur lyases. The sys…

Key takeaways

L-cysteate sulfo-lyase belongs to engineering; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect L-cysteate sulfo-lyase to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of L-cysteate sulfo-lyase from memory before moving on to harder problems.

Reference excerpt

The enzyme L-cysteate sulfo-lyase (EC 4.4.1.25) catalyzes the reaction

L-cysteate + H2O = hydrogensulfite + pyruvate + NH3 (overall reaction) (1a) L-cysteate = hydrogensulfite + 2-aminoprop-2-enoate (1b) 2-aminoprop-2-enoate = 2-iminopropanoate (spontaneous) (1c) 2-iminopropanoate + H2O = pyruvate + NH3 (spontaneous) This enzyme belongs to the family of lyases, specifically the class of carbon-sulfur lyases. The systematic name of this enzyme class is L-cysteate bisulfite-lyase (deaminating; pyruvate-forming). Other names in common use include L-cysteate sulfo-lyase (deaminating), and CuyA.

References

Denger K, Smits TH, Cook AM (2006). "L-Cysteate sulpho-lyase, a widespread pyridoxal 5′-phosphate-coupled desulphonative enzyme purified from Silicibacter pomeroyi DSS-3(T)". Biochem. J. 394 (Pt 3): 657–64. doi:10.1042/BJ20051311. PMC 1383715. PMID 16302849.

Worked examples

Example 1 — a first encounter with L-cysteate sulfo-lyase

Start with the simplest possible case. Write down what L-cysteate sulfo-lyase claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In engineering, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to L-cysteate sulfo-lyase before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about L-cysteate sulfo-lyase ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of L-cysteate sulfo-lyase

In research: L-cysteate sulfo-lyase appears in engineering research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses L-cysteate sulfo-lyase in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: L-cysteate sulfo-lyase is common in secondary-school and first-year university syllabi. It links to neighbouring topics EC 4.4.1, Enzyme stubs, Enzymes of unknown structure, so understanding it makes those chapters shorter.
In everyday life: Look for L-cysteate sulfo-lyase outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study L-cysteate sulfo-lyase in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what L-cysteate sulfo-lyase means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain L-cysteate sulfo-lyase out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is L-cysteate sulfo-lyase in simple terms?

The enzyme L-cysteate sulfo-lyase (EC 4.4.1.25) catalyzes the reaction L-cysteate + H2O = hydrogensulfite + pyruvate + NH3 (overall reaction) (1a) L-cysteate = hydrogensulfite + 2-aminoprop-2-enoate (1b) 2-aminoprop-2-enoate = 2-iminopropanoate (spontaneous) (1c) 2-iminopropanoate + H2O = pyruvate…

Why does L-cysteate sulfo-lyase matter?

Because it connects several engineering ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study L-cysteate sulfo-lyase?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on L-cysteate sulfo-lyase.