New clue into bug breaking
doi:10.1038/nindia.2008.317 Published online 11 November 2008
The bacterial cell divides due to a force generated in a ring like structure made of protein filaments and other cellular chemicals. A group of researchers has now put forward a model that will be useful in designing new antibiotics that could halt cell division of bacteria1. This might help design new weapons to tame unruly antibiotic-resistant bacteria.
The researchers studied the rod-shaped bacteria Escherichia coli that inhabit the human gut. They found that filamenting temperature sensitive Z (FtsZ) protein, anchor proteins (protein that links FtsZ to cell wall), and guanosine triphosphate (GTP) work in concert to generate a stress. FtsZ proteins form a ring like structure known as Z ring. When FtsZ mediated hydrolysis convert GTP to GDP (guanosine diphosphate) in the outer layer of Z ring, the outer layer tends to bend. But the intact GTP of inner layer resists immediate bending. This generates a stress, which is transmitted to the cell wall via the anchor proteins.
The stress generates a contractile force of few piconewtons (one trillionth of a Newton). This fuels inward movement of the cell wall at the mid-section of bacterial cell coupled with generation of a septum made of peptidoglycan consisting of sugars and amino acids. This divides a bacterial cell into two halves.
"This model offers a plausible explanation for the contraction of Z-ring, which seems to drive the constriction at the mid-cell," says lead researcher Anirban Sain. New routes, such as targeting the Z ring, to stop bacterial proliferation have become urgent since antibiotic resistance is on the rise, he adds.
The authors of this work are from: Physics Department, Indian Institute of Technology–Bombay, Powai, Mumbai, India, Theoretical Physics Division, Bhabha Atomic Research Center, Trombay, Mumbai, India.
- Ghosh, B. et al. Origin of Contractile Force during Cell Division of Bacteria. Phys. Rev. Lett. 101, 178101 (2008) | Article |