Tag Archives: Adele-Gonsalvez

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The mother of monsters chooses love not war

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by Adele Gonsalvez

In Greek mythology, Echidna is known as the “mother of monsters” and is a feared half-woman/half-serpent. However, her possession of mammalian and reptilian traits may be the only similarity between her and her animal namesake. In fact, even when provided with all the weaponry for chemical warfare, the short-beaked echidna has opted for a different route.

The short-beaked echidna is one of five extant monotreme species, and as the evolutionary offshoot of mammals, monotremes possess a suite of unique and interesting features. From being egg-laying mammals to electroreception, the book on monotreme fun facts practically writes itself. One particularly cool feature of the monotreme lineage, is the possession of a crural system – a system used to deliver venom that consists of a hollow keratinous spur connected to a crural gland on their hind limbs. These spurs regress in female platypuses and echidnas but are retained in adult males of both species. The monotreme ancestor of the platypus and echidna also possessed this crural system and venom production. The ability to produce venom has been maintained in the platypus, who is one of only fifteen experimentally confirmed venomous mammals globally. Platypus venom is used by males against other male platypuses during the breeding season, to cause paralysis in their competition and give them a reproductive edge.

But the echidna?
Not so much.

Despite being gifted the capabilities of venom production from their monotreme ancestor, these walking pin cushions have chosen a less toxic approach to their sister lineage. Echidnas have instead repurposed their crural system to aid in chemical communication. The chemical cues produced assist their social interactions and help with mate attraction. Chemical communication is renowned across many taxa as a great tool for finding a buddy in the breeding season, and echidnas are known to use cloacal odours for this purpose as well. So yes, echidnas really did repurpose a system capable of paralysis and immense pain just to up their scent game.

Echidna spur secretions appear as a milky substance at the base of the spur (for males) or in the pit previously occupied by the spur (in females). Spur secretions also differ between the sexes, with a greater quantity and number of compounds found in those produced by males. And just like the seasonal upregulation of platypus venom, secretions produced by the echidna crural system are also upregulated during their breeding season.

So, add it to the list of fun facts: echidnas choose love not war. Even when handed the ancestral capabilities of venom production, the echidna has chosen a more peaceful approach to aid their reproductive fitness. Saying “no thanks” to being toxic and producing attractive chemical cues instead? I don’t know about you, but to me, that sounds like a monster of a good idea.

Author

Adele Gonsalvez  (PhD Student) is using a variety of ‘omics resources to investigate the unique genes, peptides and traits of Australia’s monotremes. This work particularly focuses on the characterisation and functional investigation of platypus venom and monotreme-specific genes, aiming to discover novel components and their functions to better understand these animals.

Marsupial cathelicidins: characterization, antimicrobial activity and evolution in this unique mammalian lineage

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Type: Journal Article

Reference: Peel Emma , Gonsalvez Adele , Hogg Carolyn J. , Belov Katherine. 2025. Marsupial cathelicidins: characterization, antimicrobial activity and evolution in this unique mammalian lineage. Frontiers in Immunology, 16 – 2025. https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2025.1524092

Abstract

Introduction: Cathelicidins are a family of antimicrobial peptides well-known for their antimicrobial and immunomodulatory functions in eutherian mammals such as humans. However, cathelicidins in marsupials, the other major lineage of mammals, have received little attention despite lineage-specific gene expansions resulting in a large and diverse peptide repertoire.

Methods: We characterized cathelicidins across the marsupial family tree and investigated genomic organisation and evolutionary relationships amongst mammals. Ancestral sequence reconstruction was used to predict ancestral marsupial cathelicidins, which, alongside extant peptides, were synthesized and screened for antimicrobial activity.

Results: We identified 130 cathelicidin genes amongst 14 marsupial species representing 10 families, with gene expansions identified in all species. Cathelicidin genes were encoded in a highly syntenic region of the genome amongst all mammals, although the number of gene clusters differed amongst lineages (eutherians one, marsupials two, and monotremes three). 32 extant and ancestral marsupial cathelicidins displayed rapid, potent, and/or broad-spectrum antibacterial and antifungal activity. Phylogenetic analysis revealed that marsupial and monotreme cathelicidin repertoires may reflect both mammals and birds, as they encode non-classical cathelicidins found only in birds, as well as multiple copies of neutrophil granule protein and classic cathelicidins found only in eutherian mammals.

Conclusion: This study sheds light on the evolutionary history of mammalian cathelicidins and highlights the potential of wildlife for novel bioactive peptide discovery.

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The error in your way: a beginner’s guide to troubleshooting command error messages

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by Adele Gonsalvez

As a bioinformatic newbie, there is a lot to wrap your head around – from understanding basic programming language to what commands you need to use. In my experience, one particular gem is when you are trying to run a command and you receive one in a series of often uninformative error messages. Troubleshooting will end up dominating your time when you are doing any kind of coding, and it can be incredibly frustrating. So, instead of swearing at your computer (although that can be therapeutic at times), here’s some handy tips I’ve picked up that can be more effective in addressing that pesky error message.

Simple spell check

It may seem like a minor issue, but in my experience most command errors come from typos, and they can be tricky to spot. Step through your command or script to ensure there aren’t any spelling mistakes or extra spaces at the end of commands. Also ensure file paths are correct, and input files exist and are correctly named.

Have a chat with ChatGPT

ChatGPT is an incredibly useful tool for troubleshooting both error messages and general command generation. Specifying the error code, ChatGPT can outline the various causes for that error message and suggests how to go about addressing the issue.

Take a break

Leave it for a couple hours. The human version of “Did you try turning it off and on again?”. Like any form of editing, if you have been staring at the same bit of text for too long, it is easy to gloss over misspelt words or extra spaces. Revisiting it later can help you find issues that you previously overlooked.

Phone a friend

Ask your co-workers to look over your command or script. It’s likely that some of them will be more experienced in bioinformatics and can shed some light on what’s going wrong. Even if none of your coworkers are familiar with coding, a fresh set of eyes can often spot little mistakes much better than your own. I once spent hours trying to solve an error in a script, which only took for my friend 30 seconds to solve (it was an extra space at the end of a command).

Happy troubleshooting!

Adele Gonsalvez (2022 Honours Student) is investigating the expression and the antimicrobial activity of defensins from the platypus and short-beaked echidna

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Should I be afraid of the humble platypus?

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by Adele Gonsalvez (2022 Honours Student)

The platypus.

Cute, cuddly, a collection of disparate animal features somehow merged into one animal?

Sure.

Venomous?

Surely not.

But alas, just when you’d thought this Australian native couldn’t get any more bizarre (being egg-laying mammals and all) you’d be surprised again. Unbeknownst to many, the platypus is venomous – in fact, one of only a handful of venomous mammals in existence. Their secret weapon is attached to the ankles of their hindfeet – a spike-like spur connected to a venom gland. By wrapping their legs around their victim, they can jab their spur in and deliver venom into that poor unfortunate soul.

Now, who could possibly on the receiving end of the platypus’ venomous spur? The answer: the platypus. That’s right – the wrath of the platypus (in venom form) is unleashed against other platypuses. Male platypuses to be precise. You see, while female platypuses are born with spurs, they lose them by one year of age, meaning only male platypuses are venomous. The males use their venom against each other when in competition during the breeding season. The solid platypus logic is that in order to increase your own mating success, it helps to get rival males out of the picture – and injecting them with venom that causes temporary limb paralysis and a lot of pain, is an effective way to achieve this.

Now, should you be adding the platypus to your “Aussie animals who can kill me” list? Not quite. Platypus venom is yet to cause any human fatalities, and platypus envenomation in humans is quite rare. But it still packs a mean punch. Excruciating pain unable to be relieved by painkillers or first aid, and symptoms including nausea and gastric pain possibly persisting for weeks, certainly doesn’t sound like an enjoyable experience. In those few cases of humans being on the receiving end of platypus venom however, it generally only occurs when humans are physically handling platypuses, often zookeepers or fisherman. So, keep your hands to yourself and you should be right.

If you are ever lucky enough to see a platypus in the wild, floating down a river or chilling on the banks, there’s no need to be afraid. Just give the little guy some personal space and you should be at no risk of experiencing platypus venom.

Unless you are another male platypus during breeding season – well, in that case…

You should be afraid.

Author

Adele Gonsalvez (2022 Honours Student) is investigating the expression and the antimicrobial activity of defensins from the platypus and short-beaked echidna.

Platypus photo by Kimberley Bateley