CARBOHYDRATE-REACTIVE, PORE-FORMING OUTER-MEMBRANE PROTEINS OF AEROMONAS-HYDROPHILA

Citation
Dm. Quinn et al., CARBOHYDRATE-REACTIVE, PORE-FORMING OUTER-MEMBRANE PROTEINS OF AEROMONAS-HYDROPHILA, Infection and immunity, 62(9), 1994, pp. 4054-4058
Citations number
35
Categorie Soggetti
Immunology,"Infectious Diseases
Journal title
ISSN journal
00199567
Volume
62
Issue
9
Year of publication
1994
Pages
4054 - 4058
Database
ISI
SICI code
0019-9567(1994)62:9<4054:CPOPOA>2.0.ZU;2-H
Abstract
Two outer membrane proteins of Aeromonas hydrophila A6, isolated in a one-step affinity chromatography process based on carbohydrate reactiv ity, were found to be pore-forming molecules in artificial planar bila yer membranes. These carbohydrate-reactive outer membrane proteins (CR OMPs; M,s, 40,000 and 43,000) were subjected to amino acid analysis. T he amino acid profiles for these two outer membrane proteins were almo st identical. A partial protein sequence of a 14-amino-acid fragment o f the 40,000-Da protein revealed homology with outer membrane porins o f Escherichia coli and A. hydrophila, CROMPs were compared with carboh ydrate-reactive porins also extracted from outer membranes of A. hydro phila A6, These porins were isolated by using standard porin purificat ion techniques (insolubility in 2% sodium dodecyl sulfate, solubility in 0.4 M NaCl, and Sephacryl S-200 gel filtration), and then Synsorb H type 2 affinity chromatography was done. The physical and functional properties of the carbohydrate-reactive porins and CROMPs were found t o be identical. On the basis of pore-forming properties in planar lipi d bilayers and channel inhibition with maltotriose solutions, a nonspe cific, general diffusion porin and a LamB-like maltoporin were identif ied in both CROMP and carbohydrate-reactive porin preparations. To our knowledge, the use of carbohydrate reactivity to isolate channel-form ing proteins from bacterial outer membranes has not been reported prev iously.