biology

Sydney Kustu

Sydney Kustu is a biology 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 Sydney Kustu rather than just read about it. In short: Sydney Govons Kustu (March 18, 1943 – March 18, 2014) was an American biologist and a professor of biochemistry at University of California, Berkeley. She is known for her pioneering research on the regulation of Nitrogen metabolism in bacteria.

Key takeaways

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

Reference excerpt

Sydney Govons Kustu (March 18, 1943 – March 18, 2014) was an American biologist and a professor of biochemistry at University of California, Berkeley. She is known for her pioneering research on the regulation of Nitrogen metabolism in bacteria.

Academic career At the early age of 15, she entered Radcliffe College, the all-female counterpart to Harvard, receiving her Bachelor of Arts degree in General Studies in 1963, making her among the first females to graduate from Harvard. She then studied as a technician with Saul Roseman at the University of Michigan, and received her doctorate in biochemistry from UC Davis in 1970, studying under Jack Preiss. She performed postdoctoral research at the UC Berkeley in the laboratory of Giovanna Ferro-Luzzi Ames. In 1973, UC Davis hired her as an assistant professor, and she was promoted to full professor in 1984. She was subsequently recruited to UC Berkeley in 1986, from which she retired in March 2010 and received Emeritus status.

Scientific contributions Among her contributions to microbial genetics and physiology, she worked on bacterial genes and how they are regulated due to the availability of nitrogen-containing compounds from their environment. She had found that strains of Salmonella typhimurium selected for utilization of D-histidine in place of L-histidine were frequently the result of mutations affecting glutamine synthetase (GS), a central enzyme in the pathways of nitrogen utilization. In a series of paradigm-altering papers, Kustu along with her students proved that regulation GS synthesis and thus bacterial utilization of various nitrogen sources are mediated by a consortium of three regulatory proteins, which she named the Ntr system (for nitrogen regulatory): NtrA, NtrB, and NtrC. These proteins interact to repress or set off the synthesis of enzymes that catalyze the multiple routes of nitrogen utilization appropriate to extant conditions of the environment. Kustu also reported that NtrA was one of the first examples of an alternative sigma factor, and thus it can be claimed that Sydney was responsible for the discovery of RpoN or sigma 54, which it later became more widely known as.

Awards and honors In 1993, Sydney was elected to the U.S. National Academy of Sciences for her contributions to the field of Genetics. Other awards include:

elected fellow of American Academy of Arts and Sciences (AAAS) (1992) elected fellow of American Academy of Microbiology Gauss Professorship (Göttingen Academy of Sciences and Humanities|Göttingen Academy of Sciences) Miller Professorship (UC Berkeley) (2005-2006) NIH MERIT award (1986-2007) NSF Visiting Professorship for Women (1984)

Death On March 18, 2014, Sydney committed suicide on her 71st birthday, by swallowing the poisonous chemical, sodium azide. She was found by a maid in a room at the Berkeley City Club, along with a note to warn authorities about the dangerous substance having been used in the room, as well as a note with her personal information such as her laptop passcode. A bottle of research-grade sodium azide, likely obtained from her former laboratory, had been left on a table with its lid tightly secured. The unusual nature of her suicide prompted a major emergency response operation to evacuate the landmarked Julia Morgan-designed building. Sodium azide is a commonly used research chemical, used as a biocide to prevent unwanted bacterial growth in stock chemicals, as well as an inhibitor of cytochrome oxidase for studying the influence of oxidative respiration in gram-negative bacteria.

References

External links Bob B. Buchanan, Jason A. Hall, and David S. Weiss, "Sydney Kustu", Biographical Memoirs of the National Academy of Sciences (2015)

Worked examples

Example 1 — a first encounter with Sydney Kustu

Start with the simplest possible case. Write down what Sydney Kustu claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In biology, 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 Sydney Kustu 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 Sydney Kustu 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 Sydney Kustu

In research: Sydney Kustu appears in biology 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 Sydney Kustu 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: Sydney Kustu is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1943 births, 2014 deaths, 2014 suicides, so understanding it makes those chapters shorter.
In everyday life: Look for Sydney Kustu 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 Sydney Kustu in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Sydney Kustu 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 Sydney Kustu out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Sydney Kustu in simple terms?

Why does Sydney Kustu matter?

Because it connects several biology 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 Sydney Kustu?

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 Sydney Kustu.