bacteria – GOLLYGEE!

10.03.2015

preserving mars

Dark streaks indicate the flow of water down Martian slopes. Photo from nasa.gov.

About a week ago, NASA presented compelling evidence of flowing water on The Red Planet. The water flows foster hope that there may yet be life to discover on Mars. Scientific American discusses the hardest part of discovering the first Martians: preventing contamination from Earth.

The problem is not exploding rockets, shrinking budgets, political gamesmanship or fickle public support—all the usual explanations spaceflight advocates offer for the generations-spanning lapse in human voyages anywhere beyond low Earth orbit. Rather, the problem is life itself—specifically, the tenacity of Earthly microbes, and the potential fragility of Martian ones. The easiest way to find life on Mars, it turns out, may be to import bacteria from Cape Canaveral—contamination that could sabotage the search for native Martians.

Certain areas of Mars are designated as “Special Regions” by the Committee on Space Research, or COSPAR, and restricted from earthly visitors. These special regions appear to have the right topography and geothermal profiles to support life. By prohibiting visitors, astronomers hope to preserve any potential extraterrestrial life. But are these designations enough to protect Martian soil and species from Earth’s most relentless invaders?

antibiotic advances

Drug resistant Staph aureus

Over on nature.com, Sara Reardon provides a brief rundown on different alternatives to traditional antibiotic treatments. These alternatives are among some of the most promising solutions to growing antibiotic resistance. Sara mentions peptides, phages, metals and gene editing techniques. Phages have been used clinically for many years especially in Eastern Europe. And metals like silver and copper have been used as antibiotics since at least the 4th century B.C. Silver in particular causes bacteria to act like zombies and kill other live bacteria after they’ve been treated.

Antibiotic peptides are commonly isolated from the skin of frogs, and also in fungi. These peptides are typically 10–50 amino acid residues long and have many cationic residues. They can act in multiple ways, but most permeabilize and disrupt cellular membranes causing bacterial contents to leak out of the cell.

Gene editing is gaining popularity as scientists makes continued improvements to CRISPR technologies. Bacteria usually use CRISPR to develop resistance to phages and viruses, but scientists are engineering ways to use this to make bacteria attack themselves. As the technology develops, some scientists believe antibiotic CRISPR systems have the potential to be much better than traditional antibiotic treatments.

Taken as a whole, development on all these fronts signals that research on new antibiotics will continue to progress, even as traditional small molecule antibiotics are becoming harder to find.

08.27.2014

do gut bacteria prevent allergies?

Intestinal tracts of germ free mice and mice given clostridia bacteria. The higher levels of mucus in the clostria tracts is thought to prevent allergens from leaking into the bloodstream.

Science News brings word of a recent PNAS report on gut bacteria and allergies. In the study, researchers gave a group of mice antibiotics to wipe out their gut microbiome. Feeding the mice peanuts after this treatment seemed to induce allergy-like responses, that weren’t observed in mice who didn’t receive the treatment. The researchers gave the mice Clostridia bacteria to replenish the microbiome, and the response diminished.

Cathryn Nagler of the University of Chicago and colleagues treated some mice with antibiotics to wipe out the animals’ gut bacteria, and then triggered an allergy-like response to peanut particles. Peanuts revved up the germ-free animals’ immune systems — but mice with normal gut bacteria didn’t have the bad reaction.

Giving germ-free mice a dose of Clostridia bacteria made the animals more like their counterparts with normal gut flora. The microbes encourage mouse cells to make mucus that helps seal up the intestines, keeping food particles from slipping into the bloodstream and riling up the immune system, the researchers found.

The researchers suggest that this might also hold true for humans.

GOLLYGEE!

Tag: bacteria (page 1 of 5)

preserving mars

antibiotic advances

do gut bacteria prevent allergies?