Tag Archives: Pathogenic Bacteria

Good vs Bad Bacteria in the Gut


Source: Aspen Clinic


Our gut microbiomes are home to several pounds of minuscule microorganisms whose jobs include helping digest our food, producing certain vitamins, regulating our immune system, and keeping us healthy by protecting us against disease-causing bacteria.

Continue reading Good vs Bad Bacteria in the Gut

How Bacteria Talk To Each Other

Updated 1/29/2016 & 6/26/2016.


Did you know bacteria ‘talk’ with one another? Although bacteria are primitive single-celled organisms, their ability to use chemical signals to communicate with each allows them to synchronize their behavior and act together much like large, multi-cellular organisms. This communication process allows pathogenic bacteria to know when they have amassed enough troops to mount a successful attack to infect a plant or animal, including humans. (Cunningham,  2001-2010) & (iBiology, 2006-2016)
Scientists call this cell to cell signaling signaling process Quorum Sensing. Each bacterium measures the concentration of its fellows by sending out a chemical signal and  ‘listening’ for the chemical signals from other like bacteria.


Pathogenic bacteria use cell signaling to monitor their density and will activate some genes only when they know that their population is large enough to make it safe to begin that activity – ie, when they know there are enough of them who can coordinate to effect changes in cellular behavior, to try to make us sick. (Cunningham,  2001-2010)
(Source: molbio.princeton.edu)
(Source: molbio.princeton.edu)
Bacteria of the same variety can also coordinate to divide into sub-populations that carry out different activities. “For example, in the late 1990s an investigation of a biofilm community, the marine bacterium Pseudoalteromonas, revealed two physiologically distinct subpopulations. In effect there was a cellular division of labor: one group stayed attached to the surface and made nutrient available to the second group, which reproduced and released daughter cells to the surrounding water.” (Cunningham,  2001-2010)
Not only do bacteria ‘talk’ with their kind, they also have the ability to communicate with other types of bacteria (inter-species communication) – and use different chemical languages for these purposes. Bacteria are apparently multilingual.  (iBiology, 2006-2016)
Pretty impressive for single cell organisms!


Pathogenic Cell-Cell Communication

(Source: www.cs.montana.edu)

In the cartoon above, various species of bacteria are represented by different colors. Bacteria can produce chemical signals (“talk”) and other bacteria can respond to them (“listen”) in a process commonly known as cell-cell communication or cell-cell signaling. This communication can result in coordinated behavior of microbial populations. (Courtesy, MSU-CBE.)

(Source: www.cs.montana.edu)






(Source: www.bibliotecapleyades.net)
(Source: www.bibliotecapleyades.net)
Molecular Biologist Bonnie Bassler decoded this Quorum Sensing process in pathogenic bacteria. She explains how they do it in this 2009 TED Talk.
Dr Bassler is a Howard Hughes Medical Institute Investigator and the Squibb Professor of Molecular Biology at Princeton University.




Here’s more of Bonnie Bassler – this time explaining the role of Quorum Sensing communication in the symbiotic relationship between luminescent bacteria (Vibrio fischeri ) and the tiny Hawaiian bobtail squid living off the coast of Hawaii.



The tiny squid’s luminescence comes from colonies of Vibrio fischeri bacteria housed in the squid’s internal light organs. These bacteria secrete a chemical that, when it reaches a sufficient concentration, stimulates the bacteria to glow. How and why they do it is fascinating.



If you’re now really hooked by this topic and want even more, here’s Dr Bassler’s longer video that the short squid-luminescent bacteria video is taken from:  Part 1: Bacterial Communication via Quorum Sensing (53:47 minutes). 








Lest you think you’re doomed to be overrun with pathogenic bacteria plotting against you, the good news is that probiotics interfere with the quorum sensing signalling agents in pathogenic bacteria.
“From the recent research, it has been concluded that quorum sensing regulates the virulence expression in probiotics which may interfere with the signalling system avoiding the onset of virulence in pathogenic bacteria.
“… The probiotic bacteria such as Lactobacillus, Bifadobacterium and B. cereus strains degrade the auto-inducers of pathogenic bacteria by enzymatic secretion or production of auto-inducer antagonists which render the quorum sensing bacteria mute and deaf.” (Brown, 2016)
Excellent news!
(Source: richmondpediatrics.ca)
(Source: richmondpediatrics.ca)



If you find it fascinating that bacteria communicate with other and want more related information, see The Soil’s Microbiome and How Do Plants Communicate with Each Other? for information on how bacteria in the soil and plants communicate with one another.


(Source: https://adamappleseed.files.wordpress.com)
(Source: https://adamappleseed.files.wordpress.com)


And see Repair the Soil’s Microbiome to Resolve the Climate Crisis for a brief video by the brilliant and ever sensible Michael Pollan.





Bassler, B. (2/2009). How Bacteria “Talk”. TED Talk video. See: https://www.ted.com/talks/bonnie_bassler_on_how_bacteria_communicate

Bassler, B. (6/10/2009).  Bacterial Communication. iBiology video. See: https://www.youtube.com/watch?v=SWgfSELnzog

Bassler, B. (2009). Bonnie Bassler (Princeton) Part 1: Bacterial Communication via Quorum Sensing. iBiology video. See: https://www.youtube.com/watch?v=saWSxLU0ME8

Brown, M. (2011). Modes of Action of Probiotics: Recent Developments. Journal of Animal and Veterinary Advances, 10:14, 1895-1900. See: http://www.medwelljournals.com/fulltext/?doi=javaa.2011.1895.1900

Cunningham, A.B., et al (Eds). (2001-2010). The Biofilms Hypertextbook. Chapter 1: Introduction to Biofilms. See: http://www.cs.montana.edu/webworks/projects/stevesbook/contents/chapters/chapter001/section006/green/page003.html

Hardin, J.R. (12/23/2013). The Soil’s Microbiome. See: http://allergiesandyourgut.com/the-soils-microbiome/

Hardin, J.R. (3/8/2014). How Do Plants Communicate with Each Other? See: http://allergiesandyourgut.com/2014/03/08/plants-communicate-soil/

Hardin, J.R. (1/29/2016). Repair the Soil’s Microbiome to Resolve the Climate Crisis. See: http://allergiesandyourgut.com/2016/01/29/4404/

iBiology. (2006-2016). Bonnie Bassler: Cell-cell communication in bacteria.  See: http://www.ibiology.org/ibioseminars/microbiology/bonnie-bassler-part-1.html



© Copyright 2016. Joan Rothchild Hardin. All Rights Reserved.


DISCLAIMER:  Nothing on this site or blog is intended to provide medical advice, diagnosis or treatment.

Factory Farming Makes Us Sick





Did you know that factory farms use 80% of the antibiotics sold in the USA? The huge farms which grow most of the meat eaten in this country keep their animals penned in filthy, crowded living conditions. To prevent these animals from becoming diseased, Big Ag farmers add low doses of antibiotics to the animals’ daily feed.
Remember your doctor’s telling you to make sure you finish the entire course of an antibiotic even if you feel better after a few days on it? The reason is to prevent the bad bacteria from becoming resistant to the drug in case you need more of it in the future. Yet Big Ag’s factory farming practices create a perfect breeding ground for producing antibiotic resistant bacteria.
Bacteria are highly adaptable. So if you don’t take the entire course of your antibiotic prescription, the pathogenic bacteria that’s made you sick can mutate into a superbug with resistance to that antibiotic.
The continuous low dosing of factory farmed animals creates the same situation for developing superbugs. Then these resistant bacteria get out of the farm grounds and into food and water supplies, where they do a great deal of harm.
(Source: foodandwaterwatch.org)
(Source: foodandwaterwatch.org)
Go to Food & Water Watch’s site to learn more about how antibiotics routinely given to factory farmed animals is harming animals, the environment and us humans. And while you’re there, sign their petition to  pass legislation to end the misuse of antibiotics on factory farms: http://www.foodandwaterwatch.org/food/factoryfarms/antibiotics/ … pic.twitter.com/IgtNKlw7bE



(Source: ww.moneymappress.com)
(Source: ww.moneymappress.com)





I haven’t chosen the most grotesque factory farming pictures to show here. Google ‘factory farming’ if you can stand to see those images.


Factory farmed chickens
Factory farmed chickens




Sow penned in a farrowing crate nursing her babies
Sow penned in a farrowing crate nursing her piglets on a factory pig farm. She can’t even turn her head to see her own babies.




Factory farming cows (Source: www.cleanwateractioncouncil.org)
Factory farmed cows (Source: www.cleanwateractioncouncil.org)






1. A “factory farm” is a large-scale industrial operation that houses thousands of animals raised for food—such as chickens, turkeys, cows, and pigs—and treats them with hormones and antibiotics to prevent disease and maximize their growth and food output.

2. Animals are fed and sprayed with huge amounts of pesticides and antibiotics, which can remain in their bodies and are passed on to the people who eat them, creating serious health hazards in humans. Ask your school to create Meatless Mondays in the cafeteria to highlight the hazards of overconsumption of meat. Sign up for Meatless Mondays.

3. The beaks of chickens, turkeys, and ducks are often removed in factory farms to reduce the excessive feather pecking and cannibalism seen among stressed, overcrowded birds.

4. A typical supermarket chicken today contains more than twice the fat, and about a third less protein than 40 years ago.

5. 2 in 3 farm animals in the world are now factory farmed.

6. Confining so many animals in one place produces much more waste than the surrounding land can handle. As a result, factory farms are associated with various environmental hazards, such as water, land and air pollution.

7. The pollution from animal waste causes respiratory problems, skin infections, nausea, depression, and even death for people who live near factory farms.

8. Dairy cows typically live to their third lactation before being culled. Naturally, a cow can live for 20 years.

9. Hog, chicken and cattle waste has polluted 35,000 miles of rivers in 22 states and contaminated groundwater in 17 states.

10. Egg-laying hens are sometimes starved for up to 14 days, exposed to changing light patterns and given no water in order to shock their bodies into molting. It’s common for 5% to 10% of hens to die during the forced molting process.

11. Worldwide, about 70 billion farm animals are now reared for food each year.

Quoted from: DoSomething.org











In this short video (3:34), Joel Salatin, an American farmer, lecturer and author whose books include Folks, This Ain’t Normal; You Can Farm; Pastured Poultry Profits; and Salad Bar Beef, describes the differences between factory farming and organic farming – and also what he calls polyface farming. The video is part of an interview with Earth Eats Host Annie Corrigan on Sunday, January 23, 2009.


Joel Salatin in an interview with Earth Eats Host Annie Corrigan on Sunday, January 23, 2009.
Joel Salatin in an interview with Earth Eats Host Annie Corrigan on Sunday, January 23, 2009.


Essentially, Salatin’s technique is to capture the sun by growing grass.  At his farm, animals eat this grass as part of a “salad-bar diet”. He pastures them in small paddocks and moves them at least once daily. This lets pigs be pigs, enjoying their “piggyness”.


Piglet helping himself to healthy food at Salatin's Polyface Farm.
Piglet helping herself to healthy food at Joel Salatin’s Polyface Farm.



Michael Pollan has written extensively on diet, the environment and food politics. His books include Cooked: A Natural History of Transformation; Food Rules: An Eater’s Manual; In Defense of Food: An Eater’s Manifesto; The Omnivore’s Dilemma: A Natural History of Four Meals; and The Botany of Desire: A Plant’s-Eye View of the World. The New York Times and the Washington Post  both named The Omnivore’s Dilemma as one of the ten best books of 2006. It also won the California Book Award, the Northern California Book Award, the James Beard Award, and was a finalist for the National Book Critics Circle Award.
He has received numerous awards, including the 2003 Humane Society of the United States’ Genesis Award for his writing on animal agriculture.
In 2003, Pollan was appointed the John S. and James L. Knight Professor of Journalism at UC Berkeley’s Graduate School of Journalism, and the director of the Knight Program in Science and Environmental Journalism. He also lectures widely on food, agriculture, health and the environment.
Michael Pollan
Michael Pollan
It is often claimed that factory farming is needed to feed the word’s population. Pollan’s answer to this assertion was presented in his 2009 book Food Rules: An Eater’s Manual.
Filmmakers Marija Jacimovic and Benoit Detalle turned Food Rules into an award-winning short (2:13) animated stop motion video. It’s narrated by Pollan himself and offers an excellent introductory crash course on what to eat and why.


From the "Food Rules" Animation Video
Half of the food we produce goes to feeding animals we raise to eat. (Source: “Food Rules” Animation Video)


As Pollan points out, half of the food we produce goes to feeding animals we raise in order to eat them.



One of Maira Kalman's illustrations for Michael Pollan’s book Food Rules
One of Maira Kalman’s illustrations for Michael Pollan’s book Food Rules








I’ll end with this thought:







DoSomething.org. 11 Facts About Animals and Factory Farms. (no date). See: https://www.dosomething.org/facts/11-facts-about-animals-and-factory-farms

Foodandwaterwatch.org/antibiotics.  See: http://www.foodandwaterwatch.org/food/factoryfarms/antibiotics/ … pic.twitter.com/IgtNKlw7bE

Jacimovic, M. (2012). Michael Pollan’s Food Rules. Animated video.  See:  http://vimeo.com/35444471

Pollan, M. (2009). Food Rules: An Eater’s Manual. See:  http://www.amazon.com/Food-Rules-An-Eaters-Manual/dp/014311638X


© Copyright 2014 Joan Rothchild Hardin. All Rights Reserved.


DISCLAIMER:  Nothing on this site or blog is intended to provide medical advice, diagnosis or treatment.