Isolation and characterization of porins from Desulfovibrio piger and Bilophila wadsworthia: structure and gene sequencing.
The outer membrane proteins of Desulfovibrio piger and Bilophila wadsworthia (Omp-DP and Omp-BW, respectively) and the genes encoding them (omp-DP and omp-BW) were isolated and characterized. Native Omp-DP and Omp-BW form a trimeric structure of approximately 120 kDa. These proteins disaggregated into monomers with a molecular weight of approximately 53 kDa after heating at 95 degrees C for 10 min. The pore-forming abilities of these oligomeric proteins demonstrated that they form small nonspecific channels with an exclusion limit of 260-300 Da. The omp-DP and omp-BW genes were cloned and sequenced. Sequence analyses revealed an open reading frame of 1,512 bp for omp-DP and 1,440 bp for omp-BW. The mature Omp-DP protein consisted of 480 amino acids and had a calculated MW of 53,290 Da. The mature Omp-BW protein consisted of 456 amino acids and had a calculated MW of 50.050 Da. Alignment of Omp-DP with Omp-BW revealed 54% homology, whereas alignment with other known porins showed a low level of homology. Analysis of the secondary structures indicated that both proteins span the outer membrane 18 times with amphipathic beta-strands. This research presents porins which were isolated and characterized for the first time from bacteria belonging to the Desulfovibrionaceae family.
Avidan
Ofir
O
The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, 52900 Ramat Gan, Israel.
Kaltageser
Elena
E
Pechatnikov
Izabella
I
Wexler
Hannah M
HM
Shainskaya
Alla
A
Nitzan
Yeshayahu
Y
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D045282:Bilophila / Q000378:metabolism*; D003901:Desulfovibrio / Q000378:metabolism*; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D018272:Porins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D017433:Protein Structure, Secondary; D016415:Sequence Alignment; D017421:Sequence Analysis; D017386:Sequence Homology, Amino Acid
D001426:Bacterial Proteins; D018272:Porins