Natures wonders: queen bee longevity from gut biome (Introduction)

by David Turell , Thursday, August 02, 2018, 21:57 (2303 days ago) @ David Turell

They have a different set of bacteria living in their guts that seem t o make the difference, since their genetics and those of the workers are the same:

https://phys.org/news/2018-08-queen-bees-microbial-fountain-youth.html

"A team of researchers including three graduate students at the University of Arizona discovered that while worker bees and queens can be genetically identical, their vastly different lifespans appear to be connected to different microbes living in their guts.

"The observed differences in gut bacteria populations, called microbiomes, could be a clue in a mystery that has vexed scientists for a long time: In two genetically identical castes, why do worker bees die after mere weeks whereas queens can live years?

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"A growing body of research suggests that in humans, so-called probiotic bacteria like Bifidobacterium and Lactobacillus are associated with health and longevity, whereas bacteria belonging to a group known as Proteobacteria often are associated with unhealthy microbial imbalances. There appears to be a similar trend in worker bees, leading the researchers to hope that bees could be used as model organisms to study the more complex assemblies of microbes that make up the microbiome in mammals, including humans.

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"In recent years, interest in the roles of gut microbes has surged. Extensive research has been aimed at disentangling the complex metabolic pathways and interactions among the cells in our body and our microbial commensals and the myriad chemical compounds they produce and exchange.

"One such molecule is butyrate, one of many short-chain fatty acids produced by microbial fermentation of dietary fiber. Short-chain fatty acids are known to have important functions ranging from hormone production to the suppression of inflammation and possibly cancer.

"Butyrate is produced in the hindguts of honey bees, via the co-metabolism of bacteria we found to deplete in aging workers and accumulate in aging queens," says Duan Copeland, a co-author and doctoral student in the UA's Department of Microbiology. "Both in honey bees and humans, butyrate is critical to gut health but also affects a broad variety of systemic health issues. It increases immunity and detoxification in bees, and it is known to influence core function in humans, including energy levels and behavior."

"'We assume that the presence of the probiotic bacteria is one component of longer life of the queen," says Patrick Maes, a fifth-year doctoral student in the Department of Entomology and Center for Insect Science at the UA. "The other is her much higher levels of vitellogenin, which remain high throughout her life. In workers, you'll see it peak early, then taper off within a few days."

"Vitellogenin is a nutrient storage molecule always abundant in the fat and blood of queens. More than simple nutrition, it acts as an antioxidant, improves immunity and suppresses inflammation.

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"'The workers will feed her only royal jelly, which they produce in specialized glands. You can think of royal jelly as a type of super food, the bee's equivalent of breast milk, supporting beneficial bacteria and containing antimicrobial peptides."

"The study suggests that royal jelly, which enhances the growth of queen-specific gut microbes, sets the queen on a trajectory toward a much longer life by shifting her gut microbiome away from that of the common worker bee. Workers, on the other hand, rely mostly on pollen as their staple food.

"Royal jelly, honey and other factors in the hive environment keep unwanted microbes at bay, says Copeland. Bees can acquire their beneficial microbes by coming in contact with food stores, their nest mates and the overall environment in the hive."

Comment: this is a complicated arrangement. How did chance evolution create such an intricate system? Hive life depends on the queen and the caste system of bees. It cannot be created stepwise getting just the right bacteria into her gut and at the same time developing the royal jelly special food. I view this as a multifactorial form of irreducible complexity.