Navigation Links
Scripps scientists find structure of a protein that makes cancer cells resistant to chemotherapy
Date:3/26/2009

r as well as Scripps Research, determined the structure of P-gp using a technique in structural biology known as x-ray crystallography, which involves making crystals of ordered arrays of protein and then blasting the frozen crystals with x-ray radiation. The atoms in the protein crystals cause the x-rays to diffract, and the scientists collect and analyze the pattern of diffraction to solve the atomic-level structure of the proteins.

"The biggest challenge was to get enough protein to purify and make crystals from it," says Stephen Aller, Ph.D., a postdoctoral fellow in Chang's laboratory and first author of the new study.

Once the scientists succeeded in performing the x-ray crystallography and solving the structure, they found that the mouse protein P-gp, which is 87 percent identical to its human counterpart, has the shape of an upside down "v" or a tipi with a large cavity inside. The cavity's interior is lined with amino acids that bind to various substances, holding them in place. The top part of the tipi resides inside the cell membrane and has two openings for substances to enter; the bottom portion sticks out inside the cell, ending in two dumbbell-shaped arms.

This overall shape is strikingly similar to that of another protein, MsbA, that transports lipids out of bacteria. This similarity suggests that P-gp works by bringing the two dumbbell-shaped arms together on the inside of the cell and opening the closed end toward the outside of the cell, essentially reversing direction of the "v" or tipi so any substance caught inside the protein's cavity is ejected from the cell.

While the new study shows another similarity between MsbA and P-gpboth binding cavities are lined with hydrophobic amino acidsit turns out that the mammalian P-gp has many more such amino acids and a greater variety of them, including aromatic amino acids that are known to bind many different substances (substances acted on by enzymes).

"Un
'/>"/>

Contact: Keith McKeown
kmckeown@scripps.edu
858-784-8134
Scripps Research Institute
Source:Eurekalert

Page: 1 2 3

Related biology news :

1. Scripps research scientists watch as individual alpha-synuclein proteins change shape
2. Scripps research team identifies key molecules that inhibit viral production
3. Historical photographs expose decline in Floridas reef fish, new Scripps study finds
4. Scripps scientists create first crystal structure of an intermediate particle in virus assembly
5. Scripps scientists develop first examples of RNA that replicates itself indefinitely
6. Scripps Research scientists shed light on how DNA is unwound so that its code can be read
7. Dolphin population stunted by fishing activities, Scripps/NOAA study finds
8. Scripps research team defines new painkilling chemical pathway
9. Scripps research scientists identify blood component that turns bacteria virulent
10. Scripps research scientists identify compounds for stem-cell production from adult cells
11. Scripps Florida scientists awarded $1.5M to fight major water and food parasites
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:12/22/2014)... DUBLIN , Dec. 22, 2014 /PRNewswire/ ... ) has announced the addition of the ... report to their offering. ... This insight provides an overview of the ... Watermarking aims to control and monitor piracy ...
(Date:12/19/2014)... , Dec. 18, 2014   LaunchKey , the ... the post-password and Internet of Things era, today announced ... The venture round was led by Metamorphic Ventures with ... Venture Partners, VegasTechFund, and others.  LaunchKey has raised $4 ... to expand its team and bring LaunchKey to market ...
(Date:12/17/2014)... 16, 2014 Research and Markets ... the "Global Chemical Sensor Market 2015-2019" ... http://photos.prnewswire.com/prnh/20130307/600769 One major trend ... for medical sensors in biomedical applications. Chemical sensors ... and correct diagnosis during surgical procedures. The Global ...
Breaking Biology News(10 mins):The Global Watermarking and Fingerprinting Markets 2LaunchKey Raises $3 Million in Additional Funding Led by Metamorphic Ventures 2LaunchKey Raises $3 Million in Additional Funding Led by Metamorphic Ventures 3Global Chemical Sensor Market 2015-2019: Key Vendors are Abbott Laboratories, Bayer, Hoffmann La-Roche, Johnson & Johnson, NGK Spark Plugs and Robert Bosch 2
... ruled out insufficient oxygen supply to the heart as ... while in a hypothermic state. , Writing in the ... Circulatory Physiology, researchers found no significant difference in the ... exposed to one hour of severe hypothermia and rats ...
... biologists at Florida State University have uncovered a specific ... the asymmetric shape or composition critical to a cell's ... help to clarify how muscular dystrophy and some cancers ... genes involved in the cell-to-cell communication that triggers the ...
... feed or corn on the cob, farmers usually leave the ... of Penn State researchers think corn stover can be used ... , "People are looking at using cellulose to make ethanol," ... Engineering. "You can make ethanol from exploded corn stover, but ...
Cached Biology News:Heart has enough oxygen to survive hypothermia, CPR crucial 2Heart has enough oxygen to survive hypothermia, CPR crucial 3Heart has enough oxygen to survive hypothermia, CPR crucial 4FSU biologists uncover mechanisms that shape cells for better or worse 2Corn waste potentially more than ethanol 2
(Date:12/22/2014)... Dec. 22, 2014  ( www.competitivehealth.com ) — Competitive ... medical bill review and advocacy service, has signed an ... WellCard Savings discount health services marketplace. 63% ... more than they expected to pay. As part of ... costs, WellCard Savings is pleased to offer medical bill ...
(Date:12/22/2014)... 22, 2014 Fertility Associates of Memphis ... Bank USA , a network of more than 20 ... partnership, patients have fast access to a national pool ... IVF . Fertility Associates of Memphis is the only ... treatment option. , Dr. William Kutteh , director ...
(Date:12/19/2014)... BioPlus Specialty Pharmacy (BioPlus), one ... of Nick Maroulis, Pharm.D. to the newly created position ... In this position, Dr. Maroulis will continue to manage ... of our multi-site pharmacies as the company expands. Dr. ... that time he has served in many different capacities ...
(Date:12/19/2014)... Dec. 19, 2014 Bina Technologies, Inc. (Bina, ... that they have been acquired by Roche (SIX: RO, ... privately held company that provides a big data platform ... (NGS) data for the academic and translational research markets. ... and will continue to focus on development of their ...
Breaking Biology Technology:WellCard Savings Announces CoPatient Medical Bill Review Service for Members 2Fertility Associates of Memphis Announces Partnership with Donor Egg Bank USA 2Fertility Associates of Memphis Announces Partnership with Donor Egg Bank USA 3BioPlus Specialty Pharmacy Promotes Dr. Nick Maroulis to Vice President of Specialty Pharmacy Services 2Bina Technologies is acquired by Roche. 2Bina Technologies is acquired by Roche. 3
... Milwaukee — Healthcare software provider Merge eFilm ... Healthcare, following a merger finalized on June 1 ... ,The new company will be headquartered in Milwaukee ... eMed will provide radiology information systems and picture ...
... recent Digital Healthcare Conference top healthcare decision makers ... patient safety, decrease medical costs, and improve the ... held in Milwaukee, Mithridion won the Governors Business ... has stated that Wisconsin lags behind the national ...
... the nation's largest series of business-to-business IT events, is coming to ... Center. The tradeshow and exposition will feature both global and Wisconsin-area ... Intel , Gateway , Juniper Networks , Agilent ... FrontRange Solutions and Road Runner Business Class ...
Cached Biology Technology:
... protein A media yield highly purified ... to analysis of other immunoglobulin classes, ... purification. Protein A binds to the ... from mammalian species. This ready-to-use, bottled ...
... bis- (3-D-Gluconamidopropyl)deoxycholamide White solid. HYGROSCOPIC. ... CHAPSO. Has reduced electrostatic interactions that do ... DEAE-cellulose. Aggregation number: 8-16. Purity: ≥95% ... O. Aggregation number 8 - 16, CMC ...
Goat Anti-Horse IgG(T) Antibody, Unconjugated...
Goat polyclonal to STMN2 ( Abpromise for all tested applications). Antigen: Synthetic peptide: AKTAMAYKEK, corresponding to C terminal amino acids 2-11 of STMN2. Entrez Gene ID: 11075 Swi...
Biology Products: