Predatory bacteria: whole new hosts found (Introduction)

by David Turell , Wednesday, September 07, 2022, 01:09 (598 days ago) @ David Turell

Review article of new findings:

https://www.scientificamerican.com/article/predatory-bacteria-are-fierce-ballistic-and-...

"Bdellovibrio microbes are bacteria-seeking torpedoes sometimes called “the world’s smallest hunters.” Only one fifth the size of a typical bacterium, they punch above their weight. An individual Bdellovibrio darts about until it happens to smash into prey. When it does, the impact is so violent that the victim reels several cell lengths and stops moving within seconds.

"Affixed to its victim ballistically, Bdellovibrio bores inside and cleans out the place like a cross-country team at a post-10K buffet. Its systems for relieving prey of their innards are so evolved (one author termed the process “exquisite molecular dissection”) that when it is finished eating, nothing is left but ghosts and membrane fragments.

"Most bacteria eat detritus or produce their own food. But since Stolp’s discovery of the hunter Bdellovibrio, scientists have come to realize predatory bacteria are diverse, important and potentially useful. They rival killers such as amoebas and viruses as cullers of the vast bacterial herds of the soil, and scientists hope that they could also be put to work in humans and animals as dynamic antibiotics.

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"Most bacterial predators don’t invade their prey like Bdellovibrio does, but their strategies can be no less inventive. Lysobacter specializes in demolition on contact and can blow up not only other bacteria but also green algae, fungi and even little squirming animals called roundworms.

"Vampirovibrio and Vampirococcus, true to their name, have cytoskeletal protrusions sometimes termed “fangs” that the sink into the bodies of prey before draining the contents. Some of these vampires are actually vegetarian: Vampirovibrio chlorellavorus hunts green algae. It’s so good at its job that it has become a pest in experimental algal bioreactors designed to produce biofuel. Once it finds its way into one of the reactors, almost 100 percent of the crop is dead within a day or two.

"Others hunt in “wolf packs.” Herpetosiphon bacteria are huge gliding filaments that can exceed a millimeter in length and are apparently lapsed algae. Under the microscope, they look like a swarm of snakes and use their collective muscle to punch holes in colonies of their prey like a battering ram or bulldozer. Once inside, they torch the village by bursting prey with disruptive chemicals while other Herpetosiphon cells form a wall to prevent escapes. They all then feast on the entrails.

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"To begin to grasp the true ecological power of predatory bacteria, a study published in mBio in April 2021 measured predators’ response to radioactively-labeled food added directly to their habitat in 15 wild sites across North America. It found that dedicated (“obligate”) predators such as Bdellovibrio and Vampirovibrio grew, metabolized and fed much faster than nonpredatory bacteria when food was abundant. And the more food there was, the more dominant they became in the ecosystem, a finding that also holds true for predatory animals.

"But bacterial predators’ significance reaches beyond ecology. The biochemical arsenals of these microbes are rich targets for biotechnology: new antibiotics are sorely needed. Scientists have already proposed and tested the idea of using whole predatory bacteria in animals—applied topically, ingested or even injected—as living antibiotics. Remarkably, they so far seem to be both safe and effective in lab animals. Resistance may prove more elusive for pathogens against wily, evolvable predators than against the static biochemical antibiotics we currently employ."

Comment: in God's eat or be eaten world these bacteria can be used just as we are now, and still, using fungus attack/defense products as antibiotics. The theodicy cranks will complain God should have made the world peaceful, but He chose not to for his own reasons. We have to work with it as it is, with our God-given brains.