engineering

Prephenate dehydrogenase

Prephenate dehydrogenase 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 Prephenate dehydrogenase rather than just read about it. In short: Prephenate dehydrogenase is an enzyme found in the shikimate pathway, and helps catalyze the reaction from prephenate to tyrosine. Nomenclature Gene: (Saccharomyces Cerevisiae) TYR1 Shikimate pathway: Arogenate/Prephenate (ADH/PDH).

Key takeaways

Prephenate dehydrogenase belongs to engineering; place it in that map before memorising details.
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Reference excerpt

Prephenate dehydrogenase is an enzyme found in the shikimate pathway, and helps catalyze the reaction from prephenate to tyrosine.

Nomenclature Gene: (Saccharomyces Cerevisiae) TYR1 Shikimate pathway: Arogenate/Prephenate (ADH/PDH). Although in the shikimate pathway arogenate and prephenate dehydrogenase catalyze different reactions, they can at times be used interchangeably.

TyrA (tyrosine A: within the tyrosine pathway) Prephenate dehydrogenase Prephenate (Nicotinamide adenine dinucleotide phosphate) dehydrogenase Prephenate dehydrogenase (NADP) NADP+ oxidoreductase

Homology This enzyme so far has been found in sixteen different organisms; twelve different kinds of bacteria (mostly cyanobacteria) and four different kinds of plants (mostly different kinds of beans). Bacteria organisms (examples): Acenitobacter calcoaceticus, Fischerella sp., Flavobacterium so., Comamonas testosteroni, and nostoc sp. Plant organisms: phaseolus coccineus, phaseolus vulgaris, vicia faba, vigna radiata

Function Present in the shikimate pathway, in the pathway to synthesize tyrosine (a non-essential amino acid in both bacteria and plants). It catalyzes the oxidative decarboxylation reaction of prephenate to 4-hydroxyphenylpyruvate.

Reaction

In enzymology, a prephenate dehydrogenase (EC 1.3.1.12) is an enzyme that catalyzes the chemical reaction

prephenate + NAD+ ⇌ {\displaystyle \rightleftharpoons } 4-hydroxyphenylpyruvate + CO2 + NADH Thus, the two substrates of this enzyme are prephenate and NAD+, whereas its 3 products are 4-hydroxyphenylpyruvate, CO2, and NADH.

Structure This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-CH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is prephenate:NAD+ oxidoreductase (decarboxylating). Other names in common use include hydroxyphenylpyruvate synthase, and chorismate mutase---prephenate dehydrogenase. This enzyme participates in phenylalanine, tyrosine and tryptophan biosynthesis and novobiocin biosynthesis. Also found in haemophilus influenzae, synechocystis (bacteria), and aquifex aeolicus (plant). However, in haemophilus influenzae, prephenate dehydrogenase is fused with the enzyme chorismate mutase. This fusion is not found in plants or animals.

Structural studies As of late 2007, two structures have been solved for this class of enzymes, with PDB accession codes PDB: 2G5C and PDB: 2PV7.

References

Illustrations

Prephenate dehydrogenase: Prephenate dehydrogenase catalysis — Prephenate dehydrogenase catalysis

Worked examples

Example 1 — a first encounter with Prephenate dehydrogenase

Start with the simplest possible case. Write down what Prephenate dehydrogenase 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 Prephenate dehydrogenase 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 Prephenate dehydrogenase 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 Prephenate dehydrogenase

In research: Prephenate dehydrogenase 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 Prephenate dehydrogenase 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: Prephenate dehydrogenase is common in secondary-school and first-year university syllabi. It links to neighbouring topics EC 1.3.1, Enzymes of known structure, NADH-dependent enzymes, so understanding it makes those chapters shorter.
In everyday life: Look for Prephenate dehydrogenase 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 Prephenate dehydrogenase in 20 minutes

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Frequently asked questions

What is Prephenate dehydrogenase in simple terms?

Prephenate dehydrogenase is an enzyme found in the shikimate pathway, and helps catalyze the reaction from prephenate to tyrosine. Nomenclature Gene: (Saccharomyces Cerevisiae) TYR1 Shikimate pathway: Arogenate/Prephenate (ADH/PDH).

Why does Prephenate dehydrogenase 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 Prephenate dehydrogenase?

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 Prephenate dehydrogenase.