RESEARCH: MEMBRANE TRANSPORT
FOLDING PROJECT #19225 PROFILE

This project looks at how similar proteins in our cells move things across their membranes. Even though two bacterial proteins, NarU and NarK, are very similar, they move nitrate/nitrite differently. By studying these differences, scientists hope to learn more about how all membrane transport works.

Note: This TLDR is a simplication and may not be 100% accurate.

A United Picture of Transporter Functions
Membrane transporters are an integral part of the cell and serve many roles across their involvement in the transport of ions, nutrients, neurotransmitters, and many drugs across cellular membranes.

There are three major classes of membrane transport proteins that facilitate the transport of various solutes.

These classes are Uniporters, which transport one solute across the membrane in one direction, Symporters, which transport two solutes across the membrane in the same direction, and Antiporters, which transfer two solutes in opposite directions across the membrane.

These classes follow different mechanisms of transport to move their solute(s) across the membrane.
Simulations for this project will be primarily focused on studying how structural differences, sequence level differences, and energetic level differences account for the difference in transport mechanisms across the two bacterial nitrate/nitrite membrane transporters NarU and NarK.

These transporters have high sequence similarity and similar solutes, yet differ in mechanism of transport.

By evaluating the differences in mechanism of transport arising in similar transporters of different classes, we hope to further improve our understanding of the controlling mechanisms behind membrane transport.

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Membrane transporter

Proteins embedded in cell membranes that facilitate the movement of molecules across them.

Membrane transporters are crucial proteins found within cell membranes. They act like gates, selectively allowing specific molecules to pass through. These molecules can include ions, nutrients, signaling molecules, and even drugs. Membrane transporters play vital roles in maintaining cellular balance, enabling nutrient uptake, removing waste products, and mediating communication between cells.

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Uniporter

A type of membrane transporter that moves one solute across the membrane in a single direction.

Uniporters are specialized membrane proteins that transport a single type of molecule across the cell membrane. They act like doorways, allowing specific substances to pass through while blocking others. Uniporter function is essential for various cellular processes, including nutrient uptake, waste removal, and maintaining ion balance.

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Symporter

A type of membrane transporter that moves two solutes across the membrane in the same direction.

Symporters are membrane proteins that facilitate the simultaneous transport of two different molecules across the cell membrane. They work like coordinated pairs, moving both substances in the same direction. This co-transport mechanism is crucial for various cellular processes, such as nutrient absorption and signal transduction.

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Antiporter

A type of membrane transporter that moves two solutes across the membrane in opposite directions.

Antiporters are membrane proteins that facilitate the exchange of two different molecules across the cell membrane. They work like counter-directional gateways, moving one substance into the cell while simultaneously expelling another out. This antiport mechanism is essential for maintaining ion balance, removing waste products, and regulating cellular pH.

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NarU

Nitrate/nitrite membrane transporter U

NarU is a bacterial membrane protein responsible for transporting nitrate and nitrite ions across the cell membrane. It plays a crucial role in nitrogen metabolism within bacteria.

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NarK

Nitrate/nitrite membrane transporter K

NarK is another bacterial membrane protein involved in nitrate and nitrite transport. It shares similarities with NarU but exhibits differences in its mechanism of action.