
TSRI Scientists Uncover Surprising Mechanism Behind Antibiotic-Resistant Bacteria LA JOLLA, CA August 20, 2015 Every year, more strains of bacteria develop resistance to the antibiotics we use to treat deadly infections. At The Scripps Research Institute (TSRI) scientists have been working to develop new forms of these drugs, including an antibiotic called arylomycin but tests have shown that it is possible for bacteria to become resistant to arylomycin, too.
Now, scientists at TSRI have discovered that the important human pathogen Staphylococcus aureus, develops resistance to this drug by switching on a previously uncharacterized set of genes.
This explains why antibiotic resistance rates in some bacteria are higher than in others, said TSRI Professor Floyd Romesberg, senior author of the new study. Resistance depends on this little set of genes that no one knew could contribute to tolerating the arylomycins.
These findings were published this week by the journal mBio.
The Not-So-Essential Protein
Arylomycin antibiotics usually stop bacteria from growing by inhibiting a protein called Type I signal peptidase (SPase), long known as an essential protein because scientists thought bacteria could not live without it.
SPase's job is to clip peptide sequences off proteins as the proteins pass from the inside of a cell to the outside to perform functions such as nutrient acquisition. Without this cleaving of the peptide postal codes, these crucial proteins cannot reach the outside of the cell and instead accumulate in the membrane and the bacterium dies.
At least, that's what scientists thought until studies in the Romesberg lab at TSRI showed that some bacteria survived even when an arylomycin targeted and inhibited SPase. To the researchers' surprise, they found that S. aureus could survive after they deleted the gene to produce SPase altogether.
We did not believe it, said Romesberg. No one would have believed SPase was not essential. If you take the wheels off a car it's not going to drive.
Their next step was to figure out how S. aureus survived without SPase.
There had to be an answer, said Arryn Craney, a TSRI research associate and first author of the new study.
Unlocking Resistance
Using DNA sequencing technology, the researchers identified a group of genes that work together to fill in for SPase.
They found that, in the absence of SPase, a protein called AyrR switches these genes on to produce proteins called AyrA and AyrBC, which can also cleave off the peptide postal-code sequences. The scientists believe this work-around may have evolved to help bacteria at times when protein secretion levels are high and SPase can't do the job alone.
We took it for granted that we knew all the steps of protein secretion, said Craney. Now we've found a way to bypass SPase.
Romesberg said this discovery shows the built-in redundancies that help bacteria survive in many environments. He said the next step in this research is to figure out how the AyrA- and AyrBC-producing genes are switched on in the first place.
Trafficking proteins through a cell is also very important for human cells, said Romesberg. All forms of life have to secrete proteins, so discovering this new step in protein secretion has important implications.
In addition to Romesberg and Craney, authors of the study, An Alternative Terminal Step of the General Secretory Pathway in Staphylococcus aureus, were Melissa M. Dix, Ramkrishna Adhikary and Benjamin F. Cravatt of TSRI. See http://mbio.asm.org/content/6/4/e01178-15
The study was supported by the National Institutes of Health (grant AI-109809) and a postdoctoral fellowship from the Natural Sciences and Engineering Research Council of Canada.
About The Scripps Research Institute
The Scripps Research Institute (TSRI) is one of the worlds largest independent, not-for-profit organizations focusing on research in the biomedical sciences. TSRI is internationally recognized for its contributions to science and health, including its role in laying the foundation for new treatments for cancer, rheumatoid arthritis, hemophilia, and other diseases. An institution that evolved from the Scripps Metabolic Clinic founded by philanthropist Ellen Browning Scripps in 1924, the institute now employs about 2,700 people on its campuses in La Jolla, CA, and Jupiter, FL, where its renowned scientists including two Nobel laureates work toward their next discoveries. The institutes graduate program, which awards PhD degrees in biology and chemistry, ranks among the top ten of its kind in the nation. For more information, see www.scripps.edu.
# # #
For information:
Office of Communications
Tel: 858-784-2666
Fax: 858-784-8136
press@scripps.edu
Most recent headlines
05/01/2027
Worlds first 802.15.4ab-UWB chip verified by Calterah and Rohde & Schwarz to be ...
01/06/2026
January 6 2026, 05:30 (PST) Dolby Sets the New Standard for Premium Entertainment at CES 2026
Throughout the week, Dolby brings to life the latest innovatio...
02/05/2026
Dalet, a leading technology and service provider for media-rich organizations, t...
01/05/2026
January 5 2026, 18:30 (PST) NBCUniversal's Peacock to Be First Streamer to ...
01/04/2026
January 4 2026, 18:00 (PST) DOLBY AND DOUYIN EMPOWER THE NEXT GENERATON OF CREATORS WITH DOLBY VISION
Douyin Users Can Now Create And Share Videos With Stun...
19/03/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
19/03/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
19/03/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
19/03/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
19/03/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
19/03/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
19/03/2026
How Chris Bolte Builds the Sound of PlayStation Games Chris Bolte '16 is a technical sound designer at Sucker Punch Productions, where he helps create the...
18/03/2026
Newly named chief product officer (CPO), Larissa G rner Meeus will return to Net Insight on May 4.
Larissa G rner Meeus will become CPO of Net Insight on May 4...
18/03/2026
SVG Europe's The Football Summit 2026 explored how the sports broadcasting i...
18/03/2026
The 2026 NAB Show kicks off one month from today and SVG is once again set to cover the show from every angle. SVG's SportsTech@NAB Show Blog is now live - ...
18/03/2026
(L-R) The cast and crew of Dead Lover at The Ray Theater for its premiere at the 2025 Sundance Film Festival. (Photo by Robin Marshall/Shutterstock for Sundan...
18/03/2026
Yamaha C7 captured in Nashville
Wiltone Productions have announced the release of Music Row Piano, a deeply sampled Yamaha C7 piano library that's been ...
18/03/2026
Bass-enhancement plug-in upgraded
Along with a steady stream of new releases, Techivation have recently been revisiting some of the older plug-ins in their ...
18/03/2026
Mix-reference plug-in overhauled
iZotope's powerful mix-referencing plug-in has just reached its third major version, and now boasts a new capture proce...
18/03/2026
Latest EZKeys 2 expansion arrives
Toontrack's staggering collection of EZKeys 2 expansions has grown once again, and the latest instalment delivers a on...
18/03/2026
Jess Ho explores the politics of food in new SBS Audio podcast For The Culture
18 March, 2026
Media releases
New SBS Audio podcast For The Culture, hosted ...
18/03/2026
Future-ready broadcasts with ATSC 3.0 and enhanced services from Rohde & Schwarz...
18/03/2026
London Calling - When The Industry Convened to Help Streaming Find its MoJo In this blog, Laura Rognoni reflects on key discussions from the Connected TV World...
18/03/2026
SMPTE Unveils 2026 NAB Show Educational Presentations
Brie Clayton March 18, 2026
0 Comments
SMPTE , the home of media professionals, technologists, a...
18/03/2026
Auditel Ad Campaign Shot on Blackmagic PYXIS 12K
Brie Clayton March 18, 2026
0 Comments
LED wall virtual production blends 12K open gate acquisition w...
18/03/2026
Brainstorm transforms productivity and sustainability with Suite 7 at NAB Show 2...
18/03/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
18/03/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
18/03/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
18/03/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
18/03/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
18/03/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
18/03/2026
SMPTE , the home of media professionals, technologists, and engineers, today unveiled its educational presentations for the 2026 NAB Show. This year SMPTE will ...
18/03/2026
Maxon, maker of powerful, approachable software solutions for creators working in 2D and 3D design, motion graphics, visual effects, gaming, and more, today ann...
18/03/2026
Digital Alert Systems
Preview
2026 NAB Show
April 19 - 22
Booth C3452
At the 2026 NAB Show, Digital Alert Systems will showcase Version 6.0 of its DASDEC ...
18/03/2026
Setplex today announced that it will showcase its complete, fully integrated Zapflex platform for the first time at the 2026 NAB Show, introducing powerful new ...
18/03/2026
THIS ANNOUNCEMENT RELATES TO THE DISCLOSURE OF INFORMATION THAT QUALIFIED OR MAY HAVE QUALIFIED AS INSIDE INFORMATION WITHIN THE MEANING OF ARTICLE 7(1) OF THE ...
18/03/2026
COW Jobs: Seeking DP for Low Budget Dramedy - Chicago
Brie Clayton March 17, 2026
0 Comments
Seeking Director of Photography for Low Budget Dramedy Fe...
18/03/2026
COW Jobs: Seeking Gaffer for Low Budget Dramedy - Chicago
Brie Clayton March 17, 2026
0 Comments
Seeking Gaffer for Low Budget Dramedy Feature Film- I...
18/03/2026
COW Jobs: Seeking Location, Sound for Low Budget Dramedy - Chicago
Brie Clayton March 17, 2026
0 Comments
Seeking Location/Sound for Low Budget Dramed...
18/03/2026
COW Jobs: Seeking Child Wrangler for Low Budget Film - Chicago
Brie Clayton March 17, 2026
0 Comments
Seeking Child Wrangler for Low Budget Dramedy Fe...
18/03/2026
Calrec Redefines Broadcast Workflows at NAB 2026 with its Most Powerful Hardware...
18/03/2026
Oscar Nominated Two People Exchanging Saliva Posted with DaVinci Resolve Studio
Brie Clayton March 17, 2026
0 Comments
DaVinci Resolve Studio handle...
18/03/2026
Boston Conservatory Presents Celebrated Musical Satire Urinetown Performances for this Center Stage production will take place at Boston Conservatory Theater ...
18/03/2026
Charlie Puth Joins Switched on Pop at Berklee NYC The Berklee alum spoke with host and Berklee NYC professor Charlie Harding for a live taping, answering audi...
18/03/2026
X-Rite Pantone Demonstrates Advanced Color Management Solutions to Support Smart...
18/03/2026
Wednesday 18 March 2026
BAFTA winner James McAvoy to star in Sky Original serie...
18/03/2026
Wednesday 18 March 2026
Sky Sports and Zuffa Boxing announce multi-year agreement for the UK and Ireland
Sky Sports and Zuffa Boxing have announced a new mult...
18/03/2026
Wednesday 18 March 2026
Sky Unveils Poster and Trailer for Original Feature Fil...