Brandon Drescher
BIO 603
http://www.bmrb.wisc.edu/metabolomics/standards/N_acetyl_D_glucosamine/lit/166661.png
Phylum Mollusca
Class Gastropoda
Subclass Opithosbranchia
Order Nudibranchia
“naked gill”
Benthic (majority)
> 6000 extant species worldwide
Soft bodies
0.25 in. to one foot in length
Dorsal ctenidia
Cerata
Gaseous exchange
Defense
Regenerative abilities
Cleptos
http://www.seaslugforum.net/images/m16918a.jpg
http://farm3.static.flickr.com/2627/3727053162_9ccfc50777.jpg
Mediterranean
Feeds on hydroids
http://www.seaslugforum.net/images/m15547a.jpg
Colonial hydroid
Holotrichous
isorhiza
nematocysts
Shaken off later
Phospholipase A2
Toxin
http://www.natuurlijkmooi.net/images/eudraca.jpg
Second most abundant organic resource
Homopolymer of N-acetyl-D-glucosamine
Normally, chitin plates must be interrupted
One condensed oval granule per vesicle in
epidermal cells
Epidermal and stomach epithelial cells
Mouth (shields) → Esophagus (cuticles) → Stomach (granules)
http://www.scielo.br/img/fbpe/bjmbr/v32n7/3500i01peq.gif
Dashed line = inhibition
PK = protein kinase
PP = protein phosphotases
Chemical fixation for SEM, TEM, light
High pressure freezing
Boiling in KOH
Immunocytochemistry
Acidic hydrolysis → glucosamine
Mass spec, gas chromatography, FT-IR
Trypsin
Proteinase K
Chitinase
Epithelial cells
with packed
spindles
EM of packed
spindles
Exocytosed spindles from epidermis surrounded
by mucus and surrounding nematocysts
A) isolated spindles in light
B) SEM; chemically fixed
C) isolated spindles; KOH
D) SEM; KOH
High resolution fibril structure
Alimentary tract
following KOH
boiling
Esophagus to
stomach
Radula and
radular pouch
(KOH)
Chitin isolated early 2007; Martin and
Walther
Further methodology used throughout 2007
Future studies with more selective species
and evolutionary work
Genetic manipulation for cell selection and
synthesis