Bacteria can multiply rapidly, potentially doubling every 20 minutes in ideal conditions but this exponential growth phase is preceded by a period known as lag phase, where no increase in cell number is seen. Lag phase was first described in the 19th Century, and was assumed to be needed by bacteria to prepare to exploit new environmental conditions - they are basically Zombies. Beyond this, surprisingly little is known about lag phase, other than bacteria are metabolically active in this period. But exactly what are bacteria doing physiologically during that time?
To fill in this knowledge gap researchers at Norwich BioScience Institutes and Campden BRI have developed a simple and robust system for studying the biology of Salmonella during lag phase. Salmonella remains a serious cause of food poisoning in the UK and throughout the EU, in part due to its ability to thrive and quickly adapt to the different environments in which it can grow. In this system, lag phase lasts about two hours, but the cells sense their new environment remarkably quickly, and within four minutes switch on a specific set of genes, including some that control the uptake of specific nutrients.
For example, one nutrient accumulated is phosphate which is needed for many cellular processes, and a gene encoding a phosphate transporter was the most upregulated gene during the first four minutes of lag phase. The cellular uptake mechanisms for iron were also activated during lag phase, and are needed for key aspects of bacterial metabolism. This increase in iron leads to a short term sensitivity to oxidative damage. Manganese and calcium are also accumulated in lag phase, but are lost from the cell during exponential growth.
This new understanding of Salmonella metabolism during lag phase show how rapidly Salmonella senses favorable conditions and builds up the materials needed for growth.
Future research to work out the regulatory mechanisms behind these processes and the switch from lag phase to exponential growth will tell us more about how Salmonella can flourish in different environments, and could point to new ways of controlling its transmission in the food chain.
- PHYSICAL SCIENCES
- EARTH SCIENCES
- LIFE SCIENCES
- SOCIAL SCIENCES
Subscribe to the newsletter
Stay in touch with the scientific world!
Know Science And Want To Write?
- How A Former Naturopath Can Help Unravel The Trickery of Alternative Medicine
- Can A New Rule Trigger A Second EU Referendum? Petition Signatures Over 10% Of Total Votes Cast
- Better Brains With Beer
- Beneficial Bacteria May Protect Breasts From Cancer
- Some Celiac Disease May Be Due To Viruses
- Finding All-Hadronic Top - Again
- What Did Earth's Ancient Magnetic Field Look Like?
- "I will lean more to the ethics of 23 and Me in that there is no state coercive force of State involved..."
- "However you might be interested to know, we have an interesting system in the Scottish Government..."
- "Right sorry that's probably based on my earlier version of the article and facebook posts. I got..."
- "There's the issue of the population. Even the Puerto Ricans that I work with have a low opinion..."
- "Good for you! Glad to see you've seen the light and are even going so far aa to pursue a degree..."
- Chemistry Can Help Roast the Perfect Coffee Bean
- What Happens To A Soccer Player’s Brain After Missing A Penalty Kick
- It’s Back to Shots for Flu Prevention
- ACSH Applauds Media Awareness of the Fentanyl Crisis
- Counting Bites Examined, to Help Decrease Food Intake
- The Safe And Unsafe Nutty Treats For Your Pup
- How to stop the United Nations from abusing its immunity
- Study examines quality of end life care for patients with different illnesses
- Improvements needed in end-of-life care for patients with organ failure
- Georgetown Institute launches real-time study of smartphone fertility app use
- After Brexit, Italy May Be Next