Brandon Drescher BIO 603 - University of North Carolina at...

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