When you hear the word "bacteria," you probably picture organisms that couldn't be seen unless they're placed under a microscope. A bacterium that has now been classified as the largest in the world ever discovered, however, needs no special tools to be visible to the naked eye. Thiomargarita magnifica, as it's called, takes on a filament-like appearance and can be as long as a human eyelash. As the BBC notes, that makes it bigger than some more complex organisms, such as tiny flies, mites and worms. It was first discovered by marine biologist Olivier Gros living on sunken mangrove tree leaves in the French Caribbean back in 2009. 

Due to the organism's size, Gros first thought he was looking at a eukaryote rather than simpler prokaryotic organisms like bacteria. It wasn't until he got back to his laboratory that he found out that it wasn't the case at all. Years later, Jean-Marie Volland and his team at the Lawrence Berkeley National Laboratory in California took a closer look at the bacterium using various techniques, such as transmission electron microscopy, to confirm that it is indeed a single-cell organism. They've recently published a paper describing the centimeter-long bacterium in Science.

Volland said T. magnifica is "5,000 times bigger than most bacteria" and is comparable to an average person "encountering another human as tall as Mount Everest." One other information Volland's team has discovered is that the bacterium keeps its DNA organized within a structure that has a membrane. In most bacteria, DNA materials just float freely in their cytoplasm. Further, it has around 6,000 billion bases of DNA. "For comparison, a diploid human genome is approximately six giga (billion) bases in size. So this means that our Thiomargarita stores several orders of magnitude more DNA in itself as compared to a human cell," said team member Tanja Woyke. 

While the scientists know that T. magnifica grows on top of mangrove sediments in the Caribbean and that it creates energy to live using chemosynthesis, which is similar to photosynthesis in plants, there's still a lot about it that remains a mystery. And it'll likely take some time before the scientists can discover its secrets: They have yet to figure out how to grow the organism in the lab, so Gros has to gather samples every time they want to run an experiment. It doesn't help that the organism has an unpredictable life cycle. Gros told The New York Times that he couldn't even find any over the past two months. 

Volland and his team now aim to find a way to grow T. magnifica in the lab. As for Gros, he now expects other teams to go off in search of even bigger bacteria, which like T. magnifica, may also be hiding in plain sight.

A team of almost 100 scientists part of the Telomere-to-Telomere (T2T) Consortium has successfully sequenced the most complete human genome yet. If you're thinking "Wait a minute — didn't scientists produce the complete human genome sequence almost two decades ago?" Well, you wouldn't be wrong. The Human Genome Project finished sequencing 92 percent of the human genome back in 2003, but the techniques available at the time left the remaining 8 percent out of reach until recent years. Thus, 200 million DNA bases remained a mystery for the longest time. 

In a series of papers published in Science, the T2T Consortium has reported how it managed to fill in almost all of the missing spots except for five, leaving only 10 million and the Y chromosome only vaguely understood. After the papers went out, the consortium's scientists have revealed on Twitter that they have figured out the correct assembly for the Y chromosome and that they will publish another paper with the latest results.

Research lead Evan Eichler from the University of Washington likened sequencing a DNA to solving a jigsaw puzzle. Scientists have to break the DNA into small parts and then use sequencing machines to piece them together. Older tools could only sequence small sections of DNA at once, so it's like solving those unnecessarily tough puzzles with tens of thousands of repetitive, almost identical pieces. Newer tools can sequence longer segments of DNA, which makes finding the correct sequence much more achievable.

To make the process less complicated, the team used a cell line from a failed pregnancy called a mole, wherein the sperm enters an egg that doesn't have its own set of chromosomes. That means the team only had to sequence one set of DNA instead of two. Then, they used a technique called Oxford Nanopore to complete assemblies of centromeres, which are dense knobs in the middle of chromosomes. Oxford Nanopore has a relatively high error rate, however, making it less than ideal for sequencing sections with repetitive DNA. For those regions, the team used another technique called PacBio HiFi, which can sequence shorter sections with 99.9 percent accuracy. 

Eichler said the previously unknown genes include ones for immune response that help us survive plagues and viruses, genes that help predict a person's response to drugs and genes responsible for making human brains larger than other primates'. "Having this complete information will allow us to better understand how we form as an individual organism and how we vary not just between other humans but other species," Eichler said. 

The consortium's work cost a few million dollars to achieve, but sequencing is getting cheaper and cheaper with new technologies. Adam Phillippy, another lead author for the studies, said the hope is for individual genome sequencing to cost as little as $1,000 within the next decade. That could make DNA sequencing a part of routine medical tests, which might help doctors create tailor-made treatments for individuals. 

If you’d like an easy way to accomplish repetitive biological experiments, the OpenLH presents a great option for automating these tasks. 

The heart of the system is the Arduino Mega-controlled uArm Swift Pro robot, which is equipped with a custom end effector and syringe pump. This enables it to dispense liquids with an average error of just .15 microliters.

A Python/Blockly interface allows the OpenLH to be set up for creative exploration, and because of the arm’s versatility, it could later be modified for 3D printing, laser cutting, or any number of other robotic duties. 

Liquid handling robots are robots that can move liquids with high accuracy allowing to conduct high throughput experiments such as large scale screenings, bioprinting and execution of different protocols in molecular microbiology without a human hand, most liquid handling platforms are limited to standard protocols.

The OpenLH is based on an open source robotic arm (uArm Swift Pro) and allows creative exploration. With the decrease in cost of accurate robotic arms we wanted to create a liquid handling robot that will be easy to assemble, made by available components, will be as accurate as gold standard and will cost less than $1,000. In addition the OpenLH is extendable, meaning more features can be added such as a camera for image analysis and real time decision making or setting the arm on a linear actuator for a wider range. In order to control the arm we made a simple Blockly interface and a picture to print interface block for bioprinting images.

We wanted to build a tool that would be used by students, bioartists, biohackers and community biology labs around the world.

The OpenLH can be seen in the video below, bioprinting with pigment-expressing E. coli bacteria.

The first thing to notice about [Bijuo]’s cat-sized quadruped robot designs (link is in Korean, Google translation here) is how slim and sleek the legs are. That’s because unlike most legged robots, the limbs themselves don’t contain any motors. Instead, the motors are in the main body, with one driving a half-circle pulley while another moves the limb as a whole. Power is transferred by a cable acting as a tendon and is offset by spring tension in the joints. The result is light, slim legs that lift and move in a remarkable gait.

[Bijuo] credits the Cheetah_Cub project as their original inspiration, and names their own variation Mini Serval, on account of the ears and in keeping with the feline nomenclature. Embedded below are two videos, the first showing leg and gait detail, and the second demonstrating the robot in motion.

There’s more than one way to make a robot cat, of course, and here’s another design that doesn’t completely evict motors from the limbs, but still manages to keep them looking sleek and nimble.

[via Let’s Make Robots]

It sounds like an overly complicated method a supervillain would use to slowly and painfully eliminate enemies — a chamber with variable oxygen concentration. This automated environmental chamber isn’t for torturing suave MI6 agents, though; rather, it enables cancer research more-or-less on the cheap.

Tasked with building something to let his lab simulate the variable oxygen microenvironments found in some kinds of tumors, [RyanM415] first chose a standard lab incubator as a chamber to mix room air with bottled nitrogen. With a requirement to quickly vary the oxygen concentration from the normal 21% down to zero, he found that the large incubator took far too long to equilibrate, and so he switched to a small acrylic box. Equipped with a mixing fan, the smaller chamber quickly adjusts to setpoints, with an oxygen sensor providing feedback and controlling the gas valves via a pair of Arduinos. It’s quite a contraption, with floating ball flowmeters and stepper-actuated variable gas valves, but the results are impressive. If it weren’t for the $2000 oxygen sensor, [RyanM145] would have brought the whole project in for $500, but at least the lab can use the sensor elsewhere.

Modern biology and chemistry labs are target-rich environments for hacked instrumentation. From DIY incubators to cheap electrophoresis rigs, we’ve got you covered.