HOME >> BIOLOGY >> NEWS
Better Binding Through Chemistry

immune system during a biological assault, and postdoctoral fellow Roger Briesewitz got the idea for their approach while studying mutant bacteria that showed enhanced affinity of rapamycin for its target, tor, a protein involved in cell cycle regulation. Certain microbes block the proliferation of competing microbes by secreting rapamycin. The "drug" rapamycin achieves inhibition in two steps: First, it binds to a presenting protein, FKBP (for FK506-binding protein), and then the drug-protein complex binds to the tor protein.

Remarkably, Crabtree says, all of the mutations that improved protein affinity were at the interface between the two proteins. No mutations were found in regions of either protein that directly bound to rapamycin. In thinking more about this unexpected result, Crabtree and his colleagues realized that their observation was related to the molecular mechanism by which small peptides, called antigens, turn on T cells. Antigens first bind to a much larger protein known as the major histocompatibility complex (MHC). X-ray crystallography studies have shown that both members of an antigen-MHC duo interact with the T-cell receptor.

"In fact, the antigen by itself has no affinity for the T-cell receptor, but when it's held by MHC, it has a very, very high affinity interaction," said Crabtree. "So, it's the presenting molecule that gives the high affinity.

"Similarly, the immune-suppressing drugs cyclosporin and FK506 have no special affinity for calcineurin--their target protein in the human cell--until they bind to large presenting proteins. In fact, when one mixes cyclosporin and calcineurin in vitro, there's no detectable binding. But when you have cyclosporin presented by a protein called cyclophilin, there is perhaps a million-fold increase in binding affinity to its target."

In a study published in the March 2, 1999, issue of the Proceedings of the National Academy of Sciences, the
'"/>

Contact: Jim Keeley
keeleyj@hhmi.org
301-215-8858
Howard Hughes Medical Institute
2-Mar-1999


Page: 1 2 3

Related biology news :

1. Better living through urban ecology
2. Better techniques needed to predict earthquake hazards, UC study finds
3. Better model of cancer development sheds light on potential angiogenesis target
4. Natural Science and Public Health: Prescription for a Better Environment
5. Better computer modeling provides a new look at large biomolecules
6. UF nutritionist: Better to vow to eat healthy for new year
7. Better "bugs" lead to cheaper ethanol from biomass
8. Diet and cancer prevention: a sampler of story ideas for 5-a-Day for Better Health Week
9. Some Atlantic Coast Beaches Are Shrinking While Floridas Beaches Better Off Than Most
10. New Polyester Products Perform Better And Are Easy To Recycle
11. Urine Tests Will Do Better Than Pelvic Exams To Save Teens From Serious Effects Of Sexually Transmitted Diseases, UCSF Analysis Shows

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:3/27/2021)... ... March 25, 2021 , ... Phlexglobal announced ... Planet Group, has selected Phlexglobal and its innovative regulatory SaaS software, PhlexSubmission, as ... a comprehensive review of five regulatory software companies, with the review team including ...
(Date:3/27/2021)... ... 25, 2021 , ... The 2021 Virtual Conference on Clinical Trial Supply-Europe ... More and more, clinical trial supply conferences are featuring speakers and forums that ... Asymmetrex’s founder and CEO, James L. Sherley, M.D., Ph.D., presented a talk ...
(Date:3/23/2021)... ... March 23, 2021 , ... G-CON Manufacturing (G-CON), the ... by Matica Biotechnology (Matica Bio), a contract development and manufacturing organization (CDMO) specializing ... the cleanroom build out for its new GMP production facility in College Station, ...
Breaking Biology News(10 mins):
(Date:3/27/2021)... ... March 24, 2021 , ... ... Life Sciences and Healthcare firms of all sizes, adds depth to its team ... specialist. Pardillo, who earned his doctorate in computational chemistry from Florida International University ...
(Date:3/27/2021)... ... March 24, 2021 , ... ABI Wellness, ... and reporting approach designed under CEO Mark Watson, today announced a webinar dedicated ... featuring guest speakers Dr. Cameron Clark, Neuropsychologist and Founder of Sharp Thinking, and ...
(Date:3/27/2021)... ... ... The Xtalks editorial team is pleased to announce the launch of the ... joined by editorial team members Ayesha Rashid, Sydney Perelmutter and Mira Nabulsi to discuss ... including insights from industry experts. , The Xtalks Life Science podcast will feature ...
(Date:3/23/2021)... Conn. (PRWEB) , ... March 23, 2021 , ... ... develops solutions for characterizing microbiome populations down to the strain level, recently unveiled ... applications. , Not all microbes are created equal: some are easy to ...
Breaking Biology Technology:
Cached News: