Iron-reducing bacteria and iron nanostructures

Iron Reducing Bacteria [IRB] are one of the most applicable microorganisms in various industrial and environmental activities. These bacteria play a main role in the natural iron transformation. They act in a reverse metabolic pathway in contrast to iron oxidizing bacteria. In the anaerobic conditions IRB are capable to use ferric ion as the final electron acceptor and reduce Fe3+ to Fe2+. What makes these bacteria interesting in bionanotechnology is that IRB are able to synthesize iron nanostructures. In this mini review we have a quick look on the diversity, metabolism, and cultivation of IRB. Finally, we discuss iron nano structures which biosynthesized by IRB

Ancient and novel forms of silver in medicine and biomedicine

Silver has been known and used as a potent antimicrobial and wound healing agent since ancient time. Silver compounds have had other ancient applications through which Greeks, Romans and Egyptians had used silver compounds as food and water preservative. Silver and silver-based antimicrobials were put away after the discovery of antibiotics. Meanwhile, with almost a century application of antibiotics, resistant microbial strains appeared and antibiotics are going to become less and less effective. Fortunately, our traditional weapon against microorganisms reemerged in a novel form to reclaim again. Silver nanoparticles [AgNPs] are well-known as potent and novel antimicrobial agents. AgNPs would disturb microbial growth through inhibiting the absorption of phosphate, collapsing the proton motive force, forming complexes with DNA, enzyme inactivation, as well as inhibition of glucose oxidation. Its follows attacking the respiratory chain, changing the permeability and potential of the cell membrane, and inducing bacteria into a viable but non-culturable [VBNC] state and eventually killing them