Nav: Home

Simple N-terminal modification of proteins

February 13, 2020

Osaka, Japan - Proteins are essential parts of organisms; thus, they are widely used in medicine, biology and chemistry. Enhancing their inherent properties by adding functional molecules to their structures is a common and important step in many fields. For example, adding fluorescent molecules allows proteins to be traced and quantified. Many different modification strategies with various advantages have been described. Osaka University researchers now report a simple N terminus-specific modification carried out under mild conditions using new reagents prepared in one step. Their findings were published online in ChemBioChem.

The N terminus is defined as the beginning of the protein chain where the amino group of the first amino acid building block is available to react. Specifically targeting the N terminus is useful as it is rarely involved in the protein folding, making it easily accessible while having minimal impact on the protein function. It is known to be a unique and ever-present site within each protein.

Inspired by previous works, the researchers screened a series of cyclic nitrogen-containing compounds and found that 1H-1,2,3-triazole-4-carbaldehyde (TA4C) derivatives can be conjugated to the N-terminus in a single step with relatively high conversions, up to 92%.

"Simplifying protein modification is a valuable development for a variety of fields," corresponding author Akira Onoda explains. "Our approach results in highly efficient site-specific labeling under mild conditions, which is important when working with sensitive biological molecules. As long as the molecule to be added contains an amino group, a reaction can be carried out to create the TA4C group in one step, which is then reactive towards the protein N terminus."

The TA4C reagents are prepared in a single step from a functional molecule with an amino group via a reaction known as the Dimroth rearrangement. A variety of amine-containing molecules were successfully used, including polyethylene glycol, biotin, and fluorescein, demonstrating the wide range of possible functionalities.

"We believe our approach will contribute as an immensely practical option to the protein modification toolbox and accelerate development in many areas which rely on protein conjugation," corresponding author Takashi Hayashi explains. "In addition, combining our approach with techniques that target other protein sites will allow multiple functions to be introduced, providing great flexibility. This will prove beneficial in a wide variety of fields including bioengineering, pharmaceuticals, and diagnostics."
-end-
The article, "Triazolecarbaldehyde reagents for one-step N-terminal protein modification" was published in ChemBioChem at DOI: https://doi.org/10.1002/cbic.201900692.

About Osaka University

Osaka University was founded in 1931 as one of the seven imperial universities of Japan and now has expanded to one of Japan's leading comprehensive universities. The University has now embarked on open research revolution from a position as Japan's most innovative university and among the most innovative institutions in the world according to Reuters 2015 Top 100 Innovative Universities and the Nature Index Innovation 2017. The university's ability to innovate from the stage of fundamental research through the creation of useful technology with economic impact stems from its broad disciplinary spectrum.

Website: https://resou.osaka-u.ac.jp/en/top

Osaka University

Related Proteins Articles:

Designer proteins
David Baker, Professor of Biochemistry at the University of Washington to speak at the AAAS 2020 session, 'Synthetic Biology: Digital Design of Living Systems.' Prof.
Gone fishin' -- for proteins
Casting lines into human cells to snag proteins, a team of Montreal researchers has solved a 20-year-old mystery of cell biology.
Coupled proteins
Researchers from Heidelberg University and Sendai University in Japan used new biotechnological methods to study how human cells react to and further process external signals.
Understanding the power of honey through its proteins
Honey is a culinary staple that can be found in kitchens around the world.
How proteins become embedded in a cell membrane
Many proteins with important biological functions are embedded in a biomembrane in the cells of humans and other living organisms.
Finding the proteins that unpack DNA
A new method allows researchers to systematically identify specialized proteins called 'nuclesome displacing factors' that unpack DNA inside the nucleus of a cell, making the usually dense DNA more accessible for gene expression and other functions.
A brewer's tale of proteins and beer
The transformation of barley grains into beer is an old story, typically starring water, yeast and hops.
New tool for the crystallization of proteins
ETH researchers have developed a new method of crystallizing large membrane proteins in order to determine their structure.
New interaction mechanism of proteins discovered
UZH researchers have discovered a previously unknown way in which proteins interact with one another and cells organize themselves.
When proteins shake hands
Protein nanofibres often have outstanding properties such as a high stability, biodegradability, or antibacterial effect.
More Proteins News and Proteins Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Uncharted
There's so much we've yet to explore–from outer space to the deep ocean to our own brains. This hour, Manoush goes on a journey through those uncharted places, led by TED Science Curator David Biello.
Now Playing: Science for the People

#556 The Power of Friendship
It's 2020 and times are tough. Maybe some of us are learning about social distancing the hard way. Maybe we just are all a little anxious. No matter what, we could probably use a friend. But what is a friend, exactly? And why do we need them so much? This week host Bethany Brookshire speaks with Lydia Denworth, author of the new book "Friendship: The Evolution, Biology, and Extraordinary Power of Life's Fundamental Bond". This episode is hosted by Bethany Brookshire, science writer from Science News.
Now Playing: Radiolab

Dispatch 1: Numbers
In a recent Radiolab group huddle, with coronavirus unraveling around us, the team found themselves grappling with all the numbers connected to COVID-19. Our new found 6 foot bubbles of personal space. Three percent mortality rate (or 1, or 2, or 4). 7,000 cases (now, much much more). So in the wake of that meeting, we reflect on the onslaught of numbers - what they reveal, and what they hide.  Support Radiolab today at Radiolab.org/donate.