All news from Pathology & Microbiology

Candida albicans Exploits Lack Of Oxygen To Cause Disease

Scientists from Umeå university have shown how Candida albicans can modulate and adapt to low oxygen levels in different body niches to cause infection and to harm the host. Studying adaption to hypoxic or anoxic niches is particularly fruitful, since it helps us to understand the pathogenicity of C. albicans and promotes the development of better therapy approaches. Details about the study can be found in a report recently published in the journal MBio, a publication of the American Society of Microbiology.

Lethal Disease By Enterohemorrhagic E. coli : Replication Is Not Necessary

The replication of a bacterial virus is not necessary to cause lethal disease in a mouse model of a food-borne pathogen called Enterohemorrhagic Escherichia coli (EHEC), according to a study published January 10 in the open-access journal PLOS Pathogens by Sowmya Balasubramanian of Tufts University School of Medicine, and colleagues. The surprising findings could lead to the development of novel strategies for the treatment of EHEC and life-threatening kidney-related complications in children.

Study Identifies Key Step In Spread Of Drug Resistance In Acinetobacter

Spotless surfaces in hospitals can hide bacteria that rarely cause problems for healthy people but pose a serious threat to people with weakened immune systems. Acinetobacter baumannii causes life-threatening lung and bloodstream infections in hospitalized people. Such infections are among the most difficult to treat because these bacteria have evolved to withstand most antibiotics. 

Now, researchers at Washington University School of Medicine have figured out a key step in the transmission of antibiotic resistance from one Acinetobacter bacterium to another. The findings, published in Proceedings of the National Academy of Sciences, open up a new strategy to safeguard our ability to treat bacterial infections with antibiotics.

Bacteria-Virus Interaction and Human Health

Patients with cystic fibrosis are often infected by Pseudomonas aeruginosa , a bacterium that infects the lungs and prevents breathing, often causing death. P. aeruginosa itself can also be infected by viruses, which can affect the clinical outcomes of cystic fibrosis patients.

Researchers have now used P. aeruginosa as a kind of 'model system' for understanding how bacteria's interactions with viruses may affect human health. Their findings, published in  mSystems , provide insight into this bacterium's diversity and immune system.

Fungal Infection In Brain: A Major Medical Challenge

Researchers report that the fungus Candida albicans can cross the blood-brain barrier and trigger an inflammatory response that results in the formation of granuloma-type structures and temporary mild memory impairments in mice. They have also found Amyloid precursor proteins which are typically present in the plaques of Alzheimer's disease. 

Genetech Over Unapproved Stem-Cell Products Linked to Infections: FDA Warns

The US Food and Drug Administration (FDA) has sent a warning letter to Genetech, Inc. in San Diego, California, over marketing "dangerous" unapproved stem-cell products and for "significant" deviations from current good tissue practice (CGTP) and current good manufacturing practice (CGMP) requirements. Some signs may have led to microbial contamination , causing serious blood infections in some patients, the FDA announced in a news release. 

Tuberculosis: Scientists Uncover Genetic Mutation Responsible for its Vulnerability

If you live in the United States, you are unlikely to come into contact with the microbe that causes tuberculosis. Your odds of encountering the microbe are so low, in fact, that risk factors for the disease can easily go unnoticed: If you happened to carry a gene that predisposed you to tuberculosis, you would not know.  New findings from Rockefeller scientists reveal that such a genetic variant indeed exists – and that it's surprisingly common.

Streptomyces Bacteria: Unmuting Large Silent Genes Lets New Molecules Production

By enticing away the repressors dampening unexpressed, silent genes in Streptomyces bacterium, at the have unlocked several large gene clusters for new natural products. Since many antibiotics, anti-cancer agents and other drugs have been derived from genes expressed in Streptomyces, the researchers hope that unsilencing genes that have not been reported in the lab will yield additional candidates in the search for new antimicrobial drugs.

Multiple Metabolic Pathways Exhibited by Sleeping Sickness Parasite

Parasitic protozoa called trypanosomes synthesize sugars using an unexpected metabolic pathway called gluconeogenesis, according to a study published in the open-access journal  PLOS Pathogens  by David Horn of the University of Dundee in the UK, and colleagues. The authors note that this metabolic flexibility may be essential for adaptation to environmental conditions and survival in mammalian host tissues.

Pathology Insights: Cholera Bacteria Make People Sick

The enormous adaptability of the cholera bacterium explains why it is able to claim so many victims. Professor Ariane Briegel from the Leiden Institute of Biology has now discovered that this adaptability is due to rapid sensory changes in the bacterium. Her research has been published in PNAS.