For all you antibacterial soap-using dummies.

Unlike (soap and other) traditional cleaners, antibacterial products leave surface residues, creating conditions that may foster the development of resistant bacteria. Alcohol-based hand sanitizers are just about as effective against germs as soap and water. They’re also easier on your skin than hand-washing, and unlike antibacterial soaps, they don’t breed antibiotic-resistant superbacteria.

The bottom line is that you shouldn’t live in fear of high-traffic surfaces. This type of contact simply isn’t the way people get sick.

2010-11-08: We are essentially back to an era with no antibiotics

This new resistance pattern has been reported in many different types of bacteria compared to previously and 10% of these NDM1-containing strains appears to be pan-resistant, which means that there is no known antibiotic that can treat it. A second concern is that there is no significant new drug development for antimicrobials.

2015-01-08: New Antibiotics Platform?

A lot of people have had similar ideas to this one, based on the fact that the overwhelming majority of bacteria in any given environmental sample can’t be readily cultured. These organisms may well be able to produce useful antibiotics and other natural products, but how will you ever be able to tell if you can’t fish any of them out? Using this on a soil sample from Maine and leaving the chip in situ for a month, a number of colonies formed. These were tested for their ability to grow outside the device in fermentation broth, and extracts of these were tested against pre-grown lawns of an S. aureus strain to look for useful antibiotic activity. Lo and behold, one extract cleared out a large spot – it turned out to come from a newly described bacterium (Eleftheria terrae, provisionally). The compound present has been named teixobactin, and here it is. So how useful is the compound? It’s active only against gram-positive organisms, which is too bad, because we could really use some new gram-negative killers (their cell membranes make them a tougher breed). But the mechanism of action turns out to be interesting: studies of S. aureus with labeled precursors showed that teixobactin is a peptidoglycan synthesis inhibitor, but extended exposure and passaging did not yield any resistant strains. That’s close to impossible if an antibiotic is binding a particular protein target – stepping on the selection pressure will usually turn up something that evades the drug. When you don’t see that, it’s often because there’s some nonspecific non-protein-targeted mechanism, which can be problematic, but teixobactin isn’t toxic to eukaryotic cells in culture (and has a favorable tox profile in mice as well). It turns out that it binds to some of the peptidoglycan precursors, lipid II and lipid III. Vancomycin has a similar mechanism (binding to lipid II), but teixobactin has a wider spectrum of activity against lipid II variants (and lipid III as well). This mechanism makes developing resistance not so straightforward – the selection pressure is more of a bounce shot than a direct hit.

2015-02-24: Antibiotics market failure

we seem willing to pay $100K or more for cancer drugs that cure no one and at best add weeks or a few months to life. We are willing to pay 1$0Ks for knee surgery that, at best, improves function but is not lifesaving. So why won’t we pay $10K for a lifesaving antibiotic?

2015-03-31: Medieval salve kills MRSA. Impressive! Not all ancient medical knowledge is homeopathic nonsense.

Take cropleek and garlic, of both equal quantities, pound them well together… take wine and bullocks gall, mix with the leek… let it stand 9 days in the brass vessel

So goes a 1000-year-old Anglo Saxon recipe to vanquish a stye, an infected eyelash follicle. If the 9th Century recipe does lead to new drugs, they might be useful against MRSA skin infections such as those that cause foot ulcers in people with diabetes. These are usually antibiotic-resistant

2016-01-23: Antibiotics synthesis

Antibiotics are generally synthesized in nature by bacteria (or other microbes) as defenses against each other. We have identified antibiotics in the lab, and thus necessarily only those made by bacterial species that we can grow in the lab. Almost all bacterial species cannot be grown in the lab using practical methods. That hasn’t changed for decades. But those bacteria grow fine in the environment, typically the soil. So… can we isolate antibiotics from the soil?

2018-05-21: Phage Therapy

3 months earlier, Patterson had suddenly fallen ill, so severely that he had to be medevaced to Germany and then to UCSD. There were several things wrong—a gallstone, an abscess in his pancreas—but the core of the problem was an infection with a superbug, a bacterium named Acinetobacter baumannii that was resistant to every antibiotic his medical team tried to treat it with. Patterson was wasted, his cheekbones jutting through his skin. Intravenous lines snaked into his arms and neck, and tubes to carry away seepage pierced his abdomen. He was delirious and his blood pressure was falling, and the medical staff had sedated him and intubated him to make sure he got the oxygen he needed. He was dying. … “We are running out of options to save Tom. What do you think about phage therapy?”

2019-11-04: CRISPR Antibiotics

An alarming number of bacteria are now resistant to one or more antibiotics, so this new line of inquiry would certainly be welcomed if it proves effective.

In their recent study, Dr. Edgell and his colleagues successfully used a Crispr-associated enzyme called Cas9 to eliminate a species of Salmonella. By programming the Cas9 to view the bacterium itself as the enemy, Dr. Edgell and his colleagues were able to force Salmonella to make lethal cuts to its own genome.

As we discover more of the benefits of our microbiota, it would also be interesting to have a solution to bacterial infections which doesn’t create problems for our “good bacteria.

2020-02-22: Antibiotics ML

So overall, this is an impressive paper. The combination of what appears to be pretty rigorous ML work with actual assay data generated just for this project seems to have worked out well, and represents, I would say, the current state of the art. It is not the “Here’s your drug!” virtual screening of fond hopes and press releases, but it’s a real improvement on what’s come before and seems to have generated things that are well worth following up on. I would be very interested indeed in seeing such technology applied to other drug targets and other data sets – but then, that’s what people all around academia and industry are trying to do right now. Let’s hope that they’re doing it with the scope and the attention to detail presented in this work.

2020-07-24: SCH-79797

Researchers have found a compound, SCH-79797, that can simultaneously puncture bacterial walls and destroy folate within their cells — while being immune to antibiotic resistance. This is the first antibiotic that can target Gram-positives and Gram-negatives without resistance

2020-08-07: Maybe the non-profit route will work

If something isn’t done now, antibiotic-resistant bacteria could kill as many as 10M people a year by 2050. A little-known Boston nonprofit could be our best hope.

2021-07-28: Biofilms are nasty

This discovery underscores how important it is to include biofilms in any studies of antibacterial compounds because being able to kill planktonic cultures bears no relation to being able to break down biofilm.

2021-10-14: Another approach is to modify bacteria to destroy the MSRA biofilms

Bacteria present a promising delivery system for treating human diseases. Here, we engineered the genome-reduced human lung pathogen Mycoplasma pneumoniae as a live biotherapeutic to treat biofilm-associated bacterial infections. This strain has a unique genetic code, which hinders gene transfer to most other bacterial genera, and it lacks a cell wall, which allows it to express proteins that target peptidoglycans of pathogenic bacteria. We first determined that removal of the pathogenic factors fully attenuated the chassis strain in vivo. We then designed synthetic promoters and identified an endogenous peptide signal sequence that, when fused to heterologous proteins, promotes efficient secretion. Based on this, we equipped the chassis strain with a genetic platform designed to secrete antibiofilm and bactericidal enzymes, resulting in a strain capable of dissolving Staphylococcus aureus biofilms preformed on catheters in vitro, ex vivo, and in vivo. To our knowledge, this is the first engineered genome-reduced bacterium that can fight against clinically relevant biofilm-associated bacterial infections.

2023-05-23: Odd that phage therapy only made progress in former soviet republics

“Phages” are little known outside the former countries of the Soviet Union, which did the most to develop the idea. In Georgia they have been part of the local pharmacopoeia for decades. (Indeed, 2023 marks the Eliava’s centenary.) Little vials containing stale-tasting liquid full of anti-bacterial viruses can be bought at pharmacies across Tbilisi. Now, as worries about antibiotic resistance build, Western firms are taking a second look.

• Uncategorized