L-form bacteria, which were first discovered in the 1930s, are morphological variants of classical bacteria that lack a cell wall. Under specialized growth conditions L-form bacteria are capable of forming a typical “fried egg” colony, which resembles a fried egg rather than the smooth appearance of a classic bacteria colony.
These bacteria are believed to form in response to cell wall stress from certain antibiotics or the body’s immune attack, and are suspected to be associated with antibiotic-resistant and persistent infections, as well as certain diseases.
“Our study provides new insight about the molecular basis of L-form bacteria, which was not previously known,” said Ying Zhang, MD, PhD, senior author of the study and professor in the Bloomberg School’s W. Harry Feinstone Department of Molecular Microbiology and Immunology. “These findings establish the framework for future research on how the identified genes and pathways interact leading to L-forms. They also have important implications for understanding the emergence of antibiotic resistance and bacterial persistence and for developing new drugs and vaccines targeting such persistent L-form bacteria for improved infection control.”
According to Zhang, L-form bacteria are difficult to study because their biology and the circumstances favoring the transition of classical bacteria into L-forms are not fully understood. In addition, specialized culture conditions are required for study. Most research on L-form bacteria was largely abandoned in the 1980s before modern molecular tools could be applied, but renewed interest in L-form bacteria has recently emerged.
For the study, Zhang and colleagues William Glover, a graduate student at the Bloomberg School, and Yanqin Yang, a senior program analyst with the Johns Hopkins School of Medicine, conducted a genome-wide gene expression analysis of L-form colonies of E. coli bacteria. They identified interesting stress genes and pathways that overlap with persisters and biofilm bacteria.
Furthermore, the authors carried out mutant screens and identified three groups of mutants with varying degrees of defect in L-form bacteria formation or survival compared to classic colonies of E. coli. Mutants that showed complete lack of L-form growth belonged to pathways related to cell envelope stress, DNA repair, iron regulation and outer membrane biogenesis. The mutants could be restored to L-form growth by their respective wild type genes, confirming their role in L-form formation or survival.
Tim Parsons | Newswise Science News
When Air is in Short Supply - Shedding light on plant stress reactions when oxygen runs short
23.03.2017 | Institut für Pflanzenbiochemie
WPI team grows heart tissue on spinach leaves
23.03.2017 | Worcester Polytechnic Institute
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
23.03.2017 | Life Sciences
23.03.2017 | Power and Electrical Engineering
23.03.2017 | Earth Sciences