When dying, bacteria share some characteristics with higher organisms. Do bacteria, like higher organisms, have a built-in program that tells them when to die?
The process of apoptosis, or cell death, is an important part of normal animal development. In a new study published March 6 in the online, open-access journal PLoS Biology, Hanna Engelberg-Kulka and colleagues (at Hadassah Medical School of the Hebrew University, Jerusalem, Israel) have described for the first time a novel cell death pathway in bacteria that is similar to apoptosis in higher organisms. They also found that this newly described apoptotic-like death (ALD) pathway was inhibited by another non-apoptotic programmed cell death (PCD) pathway, mediated through the mazEF toxin-antitoxin system. 08.20.2009 - New images capture cell's ribosomes at work, could aid in molecular war against disease. By Sarah Yang, Media Relations | 20 August 2009 BERKELEY — Researchers at the University of California, Berkeley, have for the first time captured elusive nanoscale movements of ribosomes at work, shedding light on how these cellular factories take in genetic instructions and amino acids to churn out proteins.
Above is an entire ribosome with its changes in position color-coded — ranging from blue, indicating no movement, to red, indicating large movements. (Cate research group, UC Berkeley image) Central dogma of molecular biology. Information flow in biological systems The central dogma of molecular biology deals with the detailed residue-by-residue transfer of sequential information.
It states that such information cannot be transferred back from protein to either protein or nucleic acid. This has also been described as "DNA makes RNA makes protein. "[3] However, this simplification does not make it clear that the central dogma as stated by Crick does not preclude the reverse flow of information from RNA to DNA, but only the reverse flow from protein to RNA or DNA.