Okay, thanks Ewa so much.

Like the other speakers, I'd like to say thank you very much to the organizers for putting

on a great meeting in a great place.

Okay, so this second talk of mine is completely different from the other one before.

It's on, I think, an interesting hydrodynamic comparison of structures and interactions

of these two glycan antibiotics, spankomycin, tyco, planin.

It's a good way of exercising hydrodynamic muscles, which is like what many of us like

to do, depending on which sort of systems our colleagues elsewhere present to us.

And this is what Mary presented to us.

Okay, these are last line of defense.

That means they use when all other antibiotics fail due to resistance and other things.

But these also have problems because folks are getting clever to these.

Right, so how can hydrodynamics contribute to this?

Right, these are small glycan antibiotics, meaning they've got sugars on them, that's

spankomycin, 1459-daltons, vancozamine with interesting methyl groups and looks like an

amine group there, glucose.

And tyco planin also has carbohydrates.

You know there's carbohydrates in these ring structures, but you look for ring oxygens.

When you've got ring oxygen, that means you've got a carbohydrate residue.

But tyco planin has also got these acyl lipid groups as well.

So it's a lipoglycan in that sense.

And they have different properties which can impact on their functionality, but they have

similar reaction mechanisms.

They both attack, again I won't go watch it here because I'm in the presence of expert

microbiologists.

So they both attack the peptid glycan membranes of gram-positive bacteria and they look for

these N-acetyl-DiAla residues near the C-terminus end.

There's numbers of bonding opportunities there on the spankomycin and tyco planin molecules.

Of course this is linked with antimicrobial resistance to these because there's sensors

on the membrane of the bacteria which can recognise this and then can induce a mutation

in the sequence which is no longer recognised by bankomycin and tyco planin.

So this is the plan here.

Bankomycin dimerisation, bankomycin effects on the BANES receptor.

We said a bit of this in a previous meeting, I think that Mary gave a talk.

But also on tyco planin assembly and also interactions with mucins which is a relevance

to oral forms of these antibiotics which are normally given intravenously or subcutaneously.

Right, so this molecule 1459daltons, some may argue otherwise but in our opinion it's

a bit too small to follow by sedimentation velocity unless you run the autosanifuge to

the limits which we don't like to do.

So we can use sedimentation equilibrium.

Actually it's nice today hearing sedimentation equilibrium experiments being done by two

or three speakers and all those patterns are beautiful, don't you think?

You don't see these in papers anymore, these real optical patterns.

There's another one down there that was taken with an old model E.

So we analysed our molecular weight data using SedFit M-Star which uses this M-Star function

and all those people who have gone through my lab as PhD students and things have had

to use this at some stage right on.

In fact with some enthusiasm because the algorithm for this started off with one of those desktop

calculators when I was a postdoc with Mike Creith and then it progressed to Fortran like

everything else in the 1980s, 1990s and then Helmer came along when he was a postdoc and