Matt Baker, Scientia Associate Professor in the School of Biotechnology and Biomolecular Science at UNSW Sydney shares his passion for nature’s oldest motor, the bacterial flagellar motor.

Q. Tell us about your passion for the bacterial flagellar motor. Where did this desire to unlock its origin come from, and what fascinates you about it?

One of my life’s biggest passions is understanding the origins of complex systems — in particular, the first swimming of bacteria. The bacterial flagellar motor is one of the most ancient motors — if not one of the most ancient ‘motors’ that exist on the planet. It’s not made by man – it’s made by evolution. When I describe it to people, I describe it as a rotary nanomachine that rotates the ‘propeller’ that makes most bacteria swim.

It’s an amazing machine that — in simple terms — can build itself, go extremely fast, and navigate its host to where its life is better. It does this under the control of a sensory system in which receptors on the outside of the bacteria respond to changing nutrient concentrations in its environment.

I’m super interested in understanding its origins. Building a deep understanding of the types of things that needed to come together to create this innovation of function is powerful, because it will enable us, as researchers, to engineer protein machines for new uses. If we understand how some components of the flagellar motor arose, and which parts of them control, for example, how they are powered, we can then perhaps engineer motors that are powered by different ions, or swim with different speeds, or react to certain environments.

Q. Your story with the flagellar motor spans decades. Tell us more about your work.

My PhD was focused on the flagellar motor, and I completed a post doctorate working in bacterial transport and later trying to build motors ourselves. We’ve discovered that its building blocks are found in many other bacterial systems, serving functions other than motion – including secretion, and energy storage and release. This allows us to investigate what conditions force the flagellar motor to adapt, and helps us understand how complex nanomachines, like the bacterial flagellar motor, can develop new functions over time.

We have built some motors by combining different parts from different species and got them to work. Now, we’re looking into whether the very first motor was powered by sodium or protons. This is important because the very first cells were ‘powered’ by an ion gradient and what that ion was helps us understand early life.

Matt’s work — to reconstruct the first flagellar motor and resurrect ancient motors and examine how they work — is being funded under the Human Frontier Science Program (HFSP) Research Grant secured in 2021.

Q. Can you paint a picture of how the flagellar motor works?

I encourage people to think about a bacterial cell being like a submarine. It has a little outboard motor on its back and a giant propeller that’s about ten times the size of a cell. It is made up of about 50 different proteins, can rotate up to 100,000 rpm, can change direction in milliseconds and helps bacteria navigate, on average, to where their lives are better.

Most bacteria ‘swim’ via a tiny nanomachine that’s one thousandth the size of a grain of sand which rotates five times faster than a Formula 1 engine. We hope to understand how this motor first came to rotate.

Read more about the bacterial flagellar motor here:

https://www.science.org/doi/10.1126/sciadv.abq2492

Sleep disorders — left unmanaged — have safety implications for our workplaces and on our roads. Drivers with sleep disorders are more than twice as likely to be involved in road traffic accidents. Sleep disorders pose a risk for poor mental health and declining physical health, too.

The Australian Raine Study found that by middle age, some 43% of middle-aged adults will have at least one sleep disorder severe enough to require clinical management such as sleep apnoea, restless leg syndrome or insomnia.

Amy Reynolds is Associate Professor (Research) at the Flinders Health and Medical Research Institute (Sleep Health) at Flinders University. Her key research focus is the experiences of shift workers living with sleep problems, many of whom are undiagnosed and untreated for extended periods.

Her most recent work has focused on the impacts of sleep disorders in young shift workers, particularly on their mental health and workplace productivity.

“Our research highlights the consequences are significant for mental health and for workplace productivity, and this starts from early in a young worker’s career. We need to do better to help young shift workers who might be at risk for a sleep disorder,” A/Prof Reynolds explains.

Asleep on the job: sleep disorders in shift workers largely undiagnosed

Having taken an in-depth look at shift workers, A/Prof Reynolds’ work has found that sleep disorders can be undiagnosed and untreated for extended periods. It’s not uncommon for shift workers to have gone more than five years before they seek help from a healthcare provider after noticing symptoms.

“Being symptomatic for years without access to effective treatments poses a potential risk for road safety and impacts the quality of life, mental health and wellbeing of our shift workers,” she says.

“We want to see this change.”

“What we know from our research here at Flinders Health and Medical Research Institute (FHMRI Sleep Health) is that many shift workers assume bad sleep is something they have to endure. They can perceive that the shift itself is the problem, instead of considering whether there is an underlying disorder that could be treated. The good news is – we can do something about this.”

Sleep disorder screening a first step, says A/Prof Reynolds

Shift workers who suspect they have symptoms of sleep disorder can take immediate action, says A/Prof Reynolds.

“We want to encourage shift workers who may be experiencing the signs and symptoms of sleep disorder to engage with screening and management. There are options available, and talking to your GP is an important first step. The AISH Sleep Health Clinic at Flinders University also has experts in sleep and circadian rhythms and can take referrals for shift workers.”

Read more about sleep disorders, including in shift workers:

Prevalence of common sleep disorders in a middle-aged community sample.

Read about the impacts of sleep disorders shift workers, particularly for their mental health and workplace productivity in A/Prof Reynolds’ most recent work:
Diagnosis and management of sleep disorders in shift workers.

Shift work, sleep disorders and mental health.

Insomnia and workplace productivity loss among young adults.

The AISH Sleep Health Clinic at Flinders University has experts in sleep and circadian rhythms.

On World Hearing Day, we look at the association between untreated hearing loss and dementia.

In 2025, an estimated 433,300 Australians are living with dementia. Without a medical breakthrough, these numbers are predicted to double by 2058*. Nearly half (45%) of dementia cases are associated with several potentially modifiable risk factors. Among these, hearing loss is estimated to account for 7% of the risk of all dementia cases worldwide, however, to date, only the ACHIEVE clinical trial study has investigated the effect of hearing intervention, reporting negative results.**

It is unclear if the reported association between hearing loss and dementia is causal, and if the clinical remediation of hearing impairment can indeed reduce the rate of cognitive decline among older adults at risk of dementia.

To address this gap, a groundbreaking Australian clinical trial named HearCog was conducted by a former Young Tall Poppy recipient Associate Prof Dona Jayakody, Audiologist and Head of Brain and Hearing at Ear Science Institute Australia. “We just finished the HearCog trial and are very excited to find out about the outcomes of the study to find out whether by treating hearing loss, we can delay the rate of cognitive decline in older people,” says A/Prof Jayakody. Hearing loss and impact on quality of life

“What we are already seeing from our Australian research studies is that hearing loss not only increases the risk of cognitive impairment and dementia; it also increases the risk of loneliness, depression, anxiety and stress and frailty, which impact quality of life of older adults.”

“When older people experience hearing loss, it affects their ability to communicate effectively with family and friends. This is particularly pronounced when older people depend upon a small network of family and friends and the communication partners are required to speak loudly, repeat conversations and so on.”

“If the conversation is broken down between two people – even between partners, the person with hearing loss becomes emotionally and socially lonely.”

Get tested: hearing tests to improve quality of life

Treating hearing loss has many benefits including improved communication and quality of life. If you are struggling to understand speech, especially in noisy environments, having difficulty hearing people on the phone, often ask people to repeat themselves etc, it is the time to get your hearing tested.

Read about Dr Jayakody’s work at Ear Science Institute at https://www.earscience.org.au/research/#brain-and-hearing

*Sources: AIHW. Dementia in Australia. Canberra: Australian Institute of Health and Welfare 2023; and Lin et al., 2023.