XML Feed for RxPG News   Add RxPG News Headlines to My Yahoo!   Javascript Syndication for RxPG News

Research Health World General
 
  Home
 
 Latest Research
 Cancer
 Psychiatry
 Genetics
 Surgery
 Aging
 Ophthalmology
 Gynaecology
 Neurosciences
 Pharmacology
  Anti-Inflammatory
  Antivirals
  Antihypertensives
  Anticholesterol
  Anti-Clotting Drugs
  Anti Cancer Drugs
  Hypnotics
  PPI
  Antibiotics
   Tigecycline
   Sirolimus
  Analgesics
  Surfactants
  Fatty Acids
  Adrenergics
  Metals
  Varenicline
 Cardiology
 Obstetrics
 Infectious Diseases
 Respiratory Medicine
 Pathology
 Endocrinology
 Immunology
 Nephrology
 Gastroenterology
 Biotechnology
 Radiology
 Dermatology
 Microbiology
 Haematology
 Dental
 ENT
 Environment
 Embryology
 Orthopedics
 Metabolism
 Anaethesia
 Paediatrics
 Public Health
 Urology
 Musculoskeletal
 Clinical Trials
 Physiology
 Biochemistry
 Cytology
 Traumatology
 Rheumatology
 
 Medical News
 Health
 Opinion
 Healthcare
 Professionals
 Launch
 Awards & Prizes
 
 Careers
 Medical
 Nursing
 Dental
 
 Special Topics
 Euthanasia
 Ethics
 Evolution
 Odd Medical News
 Feature
 
 World News
 Tsunami
 Epidemics
 Climate
 Business
 
 India
Search

Last Updated: Nov 18, 2006 - 12:32:53 PM

Antibiotics Channel
subscribe to Antibiotics newsletter

Latest Research : Pharmacology : Antibiotics

   DISCUSS   |   EMAIL   |   PRINT
Two-component lantibiotic with therapeutic potential discovered
Oct 31, 2006 - 4:13:00 PM, Reviewed by: Dr. Priya Saxena

"Having the ability to make analogs of these naturally occurring antibiotics gives us the flexibility to look for improvements in properties such as toxicity, biostability and bioavailability"

 
The discovery and preparation of a naturally occurring antibiotic could open the door to new therapeutic drugs for treating nasty infections.

The rapid spread of drug-resistant bacterial strains poses a persistent threat to human health, and requires new sources of antibiotics to treat infections. Researchers at the University of Illinois at Urbana-Champaign are tackling this problem by discovering and preparing natural antibiotics called lantibiotics.

Lantibiotics are a class of very potent antimicrobial compounds whose antimicrobial properties are attributed to their structure. They possess unusual sulfur bridged rings that provide structural rigidity for binding their cellular targets. Lantibiotics are commonly used in the food industry to inhibit the growth of microorganisms.

"Having the ability to make analogs of these naturally occurring antibiotics gives us the flexibility to look for improvements in properties such as toxicity, biostability and bioavailability," said Wilfred van der Donk, a William H. and Janet Lycan Professor of Chemistry at the U. of I. He is a corresponding author of a paper that will be posted online this week ahead of regular publication by the Proceedings of the National Academy of Sciences. In previous work, van der Donk first identified the molecular activity of an enzyme (LctM) responsible for naturally turning a small protein into a lantibiotic. That discovery, reported in the journal Science in 2004, involved lacticin 481, a lantibiotic produced by several strains of Lactococcus lactis, a bacterium used in cheese production.

In March 2006, van der Donk's team reported, again in Science, the synthesis of the lantibiotic nisin. The most studied lantibiotic, nisin has been used as a food preservative for more than 40 years without the development of significant antibiotic resistance.

Then, in the Oct. 26 issue of Chemistry and Biology, the team demonstrated that LctM could accept substrates vastly different from its natural substrate, in vitro.

"Normally, enzymes are very selective, and will work only on their natural substrate," said van der Donk, who is also an affiliate of the university's Institute for Genomic Biology. "We showed that our enzyme could modify many synthetic substrates, and produce sulfur bridged rings of different sizes and shapes. This offered us the opportunity to control and alter the structure of lantibiotics."

In their latest work, to be published in PNAS, van der Donk and his collaborators describe a new two-component lantibiotic. These lantibiotic systems utilize two peptides that are each post-translationally modified to an active form, and act in synergy to provide antibacterial activity.

"Given the synergy observed among two-component lantibiotics, which display similar or higher activity than the best single-component lantibiotic, nisin, the possibility of engineering new lantibiotics with therapeutic potential is even greater for these systems," van der Donk said.

Using bioinformatics, the researchers found genes annotated in the fully sequenced genome of the Gram-positive bacterium Bacillus halodurans C-125 as precursors of the lantibiotics mersacidin and cytolysin. This strain had not previously been reported to produce a lantibiotic.

The new two-component lantibiotic was named haloduracin by its discoverers. "The bacterium that produces haloduracin grows at pH 9 and above, suggesting that the lantibiotic it produces will be stable in the human body, unlike nisin, which is unstable at pH 7 and above," van der Donk said. Significantly, the researchers succeeded in expressing in the bacterium Escherichia coli the machinery to produce haloduracin, thereby creating the first in vitro biosynthesis of a two-component lantibiotic.

"The in vitro biosynthesis opens the door to new, intriguing possibilities involving antimicrobial peptide design and engineering," van der Donk said. "Now we can start applying all the lessons we learned with lacticin 481."
 

- Oct. 26 issue of Chemistry and Biology
 

www.uiuc.edu

 
Subscribe to Antibiotics Newsletter
E-mail Address:

 

The work was funded by the National Institutes of Health.

Related Antibiotics News

Two-component lantibiotic with therapeutic potential discovered
Antibiotic inhibits cancer gene activity
Rapamycin shown to inhibit angiogenesis
Tigecycline, world�s first glycylcycline expanded broad-spectrum antibiotic, launched in UK
FDA Warns of Liver Failure With Telithromycin
What is the optimal duration of antibiotic therapy?
Should children with suspected meningitis be given antibiotics before transfer to hospital?
Production Practices Effect Antimicrobial Resistance in Poultry
Aspirin Protects Against Aminoglycoside Induced Hearing Loss
Avelox (Moxifloxacin) is as effective as Levofloxacin combination therapy for severe community-acquired pneumonia


For any corrections of factual information, to contact the editors or to send any medical news or health news press releases, use feedback form

Top of Page

 

© Copyright 2004 onwards by RxPG Medical Solutions Private Limited
Contact Us