Achilles’ heel found in antibiotic-resistant bacteria -Science Codex

UEA researchers discover Achilles’ heel in antibiotic-resistant bacteria

Posted June 18, 2014 – 5:30pm

Scientists at the University of East Anglia have made a breakthrough in the race to solve antibiotic resistance.

New research published today in the journal Nature reveals an Achilles’ heel in the defensive barrier which surrounds drug-resistant bacterial cells.

The findings pave the way for a new wave of drugs that kill superbugs by bringing down their defensive walls rather than attacking the bacteria itself. It means that in future, bacteria may not develop drug-resistance at all.

The discovery doesn’t come a moment too soon. The World Health Organization has warned that antibiotic-resistance in bacteria is spreading globally, causing severe consequences. And even common infections which have been treatable for decades can once again kill.

Researchers investigated a class of bacteria called ‘Gram-negative bacteria’ which is particularly resistant to antibiotics because of its cells’ impermeable lipid-based outer membrane.

This outer membrane acts as a defensive barrier against attacks from the human immune system and antibiotic drugs. It allows the pathogenic bacteria to survive, but removing this barrier causes the bacteria to become more vulnerable and die.

New research reveals an Achilles’ heel in the defensive barrier which surrounds drug-resistant bacterial cells. The findings pave the way for a new wave of drugs that kill superbugs by bringing down their defensive walls rather than attacking the bacteria itself. It means that in future, bacteria may not develop drug-resistance at all.

(Photo Credit: Diamond Light Source)

Until now little has been known about exactly how the defensive barrier is built. The new findings reveal how bacterial cells transport the barrier building blocks (called lipopolysaccharides) to the outer surface.

Group leader Prof Changjiang Dong, from UEA’s Norwich Medical School, said: "We have identified the path and gate used by the bacteria to transport the barrier building blocks to the outer surface. Importantly, we have demonstrated that the bacteria would die if the gate is locked."

"This is really important because drug-resistant bacteria is a global health problem. Many current antibiotics are becoming useless, causing hundreds of thousands of deaths each year.

"The number of super-bugs are increasing at an unexpected rate. This research provides the platform for urgently-needed new generation drugs."

Lead author PhD student Haohao Dong said: "The really exciting thing about this research is that new drugs will specifically target the protective barrier around the bacteria, rather than the bacteria itself.

"Because new drugs will not need to enter the bacteria itself, we hope that the bacteria will not be able to develop drug resistance in future."

Source: University of East Anglia


Dr. Malcolm Hargraves and the Out-of-Doors

1,400 programs over 28 years…

by Harley Flathers, Rochester, MN Post Bulletin Thursday, April 24, 2014

The 6 o’clock evening introduction was very simple for a great Rochester conservationist. “It’s time for you and the Out-of-Doors with Dr. M.M. Hargraves, presented by the Izaak Walton League. And now, here is Dr. Hargraves.” I did that intro many times on Saturday evenings on KROC radio, a program that started under the guidance of program director Cal Smith in 1944. And after more than 1,400 programs over 28 years, Cal and other friends were in the studio for his last show. That aired Saturday, April 15, 1972.

In a Post-Bulletin column by Gordon Yeager running that final day, he wrote, “You and the Out-of-Doors has been the conservation conscience of Rochester and area listeners.”

An authority on blood diseases at Mayo Clinic, Hargraves was a longtime member of the Izaak Walton League and a national honorary chairman of that group years earlier. The show first aired semi-monthly on Friday evenings, then soon became a weekly staple at 6 p.m. Saturdays. Occasionally Mrs. Hargraves would join him to discuss outdoor cooking and wild food sources and preparation.

Dr. Malcolm Hargraves taped his program usually without a script, sometimes from his home and at his Wisconsin cabin. The reel tape was mailed to the studios by special delivery. Occasionally, his guest list included a well-known local, area or national conservationist. He was an authority on mushrooms and an internationally known hematologist. In the mid-1940s, Dr. Hargraves was recognized for discovering a cell (the Hargraves Phenomenon), which served as diagnostic evidence of the presence of the disease complex known as systemic lupus erythematous.

An avid outdoorsmen, he also was a farmer and ecologist serving on the Water Pollution Commission for 14 years, seven of those years as president. He could speak about robins or mushrooms, especially the edibility of a wild mushroom. Many listener responses gave him topics for the air. But finally “it is the eternal deadline that is the principal reason of ending the long series on the air. Seems it always gets right down to Saturday before I get around to do research and get the taping done. I’m glad to be rid of the deadline” concluded the pioneer conservationist.

I recall the good Dr. Hargraves often coming to the studio with a tape in hand at five minutes before 6 p.m. or telling me, “I’ll do it live,” which meant I would record it for him to take along. He and Mildred (his wife) often chatted briefly with me before or after the show. And I guess Mildred took a liking to me because when he died at age 77 on March 29, 1981, in Chatfield she asked me to do an eulogy during his funeral at Christ United Methodist Church in Rochester.

Dr. Hargraves was on the Mayo Clinic staff from 1938 to 1968. Outside of his clinical work, he helped develop the Minnesota Volunteer Program for the Youth, served on the state board of Planned Parenthood and helped open the Planned Parenthood office in Rochester in 1971. Through the years, Dr. Hargraves received many awards for his role in public health by preservation of the quality of water resources in Minnesota. In 1967, the Minnesota Sertoma Club presented him with a “Service to Mankind Award.” And in 1968, former Gov. Harold Levander presented him a citation for distinguished service to the state of Minnesota.

Hargraves’ life filled two careers, first through Mayo Clinic and secondly as a well known conservationist. When he retired in 1972 from the KROC radio program, we gave him and the Izaak Walton League a silver tray inscribed with “Thanks for a lifetime of service.”

Next week: Rochester’s First National Bank (Now U.S. Bank) is 150 years old.

Harley Flathers is a longtime Rochester-area broadcaster and historian. Got a comment for Harley? Send it to news or to Harley at Post-Bulletin, P.O. Box 6118, Rochester, MN 55903. His column runs on Thursdays.

Greenland Daily Melt June 17th, 2014