Bacteria have a unique way of changing the structure of cells, say researchers

By John C. O’Sullivan, APB Senior ScientistScience article A family of bacteria known as Gram-negative bacteria have a special way of altering the structure and function of cells.
The new study shows that they do so by changing the cellular structure of the DNA of the cells themselves.
In a study published in the Proceedings of the National Academy of Sciences, researchers found that Gram-positive bacteria alter the shape of the genetic material in DNA and RNA molecules by altering the arrangement of the nucleotides within the DNA and by changing their structure.
The researchers call the new behavior a “parsimonious” DNA folding, or DNA-like folding.
The authors of the study believe that this kind of DNA folding allows bacteria to change the structural properties of DNA at a molecular level.
This is a key feature of cellular processes that are important for life, and it’s a fundamental feature of evolution.
The study also found that the ability of these bacteria to do this is limited by the complexity of their DNA and that the new information can only be acquired by manipulating the DNA sequence.
This work is a major advance in understanding how bacteria and other living systems interact and evolve.
The work, led by Harvard University geneticist William J. Riedel, could potentially be used to develop a way to make cells more complex, which could lead to the development of more complex and useful new drugs and medical devices.
“This is a tremendous advance in our understanding of the way bacteria interact and change the structure, function and DNA of their cell,” Riedels said.
“The research shows that a small number of Gram-Positive bacteria may be able to accomplish this kind for the first time.
The fact that we can change the shape and function in this way, even in a single cell, is an important milestone in understanding the complexity and evolution of cell biology.”
The researchers found their first evidence of the parsimonous DNA folding after a group of Gram‐positive bacteria isolated from the intestinal tract of two mice, and then sequenced the DNA.
In addition to the genome sequence, they were able to isolate a small section of DNA that contained information about the bacteria’s genetic structure.
They then compared this information with a sequence of genes that normally code for proteins that are required for the cell’s survival and function.
They found that these bacteria had a “nonparsular” (nonfunctional) DNA folding that allowed them to change DNA by altering its arrangement.
The researchers then used the technique to generate the bacterial genome sequence.
The bacteria, they found, also had an unusual DNA sequence that had a different pattern of repeating nucleotide sites, or repeats.
In contrast, the sequence of the genes of the other Gram‐negative bacteria had the same repeat patterns.
This pattern of DNA repeating repeats is known as a pseudocoding site, and this is how the pseudocoded DNA is usually used to code for the proteins in the cell.
In addition, the bacteria showed a very specific way of editing their genome, by inserting or deleting specific nucleotids into the DNA at specific positions in the genome.
They also used a technique known as “transcriptional DNA modification” to make these changes.
They sequenced these sequences and found that they were all very similar.
“Our analysis showed that these Gram‐Positive organisms were able and willing to alter the DNA sequences of the bacterial genomes, by altering a specific section of the genome that they could modify,” Riesel said.
He said that this modification could also be used for making other kinds of DNA, like RNA, and RNA is the main protein in cells that encode proteins.
“We are beginning to see that the Gram‐Negative bacteria can use this unique DNA-folding technique to alter DNA sequence and to alter cell function,” Riels said.
Riedels and his colleagues also found in the study that the bacterial DNA is not just one particular section of a single gene.
Rather, it is a large, complex network of genetic sequences, known as an RNA-like strand.
RNA is a chemical molecule that can encode and change specific functions.
“These RNA sequences were very similar to the sequences that are present in the DNA,” Riegles said.
RNA-based DNA-binding proteins are proteins that have been designed to bind specific RNA molecules, or short strands of DNA.
Riesels and other researchers have shown that RNA-binding protein complexes are essential for the cellular function of many types of cells including the gut, the liver and other tissues, and they may be crucial for the survival and survival of many other living organisms.
Riesels said that there is no evidence yet that the modified DNA of Gram–negative bacteria is a good source of genetic material for the Gram-Negative species.
However, this finding opens the door to developing new ways to modify the DNA structure of bacteria, or to using DNA