caa a22 4500 467943516 CHVBK 20180405193734.0 cr unu---uuuuu 170328e20041001xx s 000 0 eng 10.1007/s10872-005-5775-4 doi (NATIONALLICENCE)springer-10.1007/s10872-005-5775-4 (NATIONALLICENCE)springer-10.1007/s10872-004-5775-9 Degradation of outer membrane proteins of Synechococcus sp. in vitro and in situ [Elektronische Daten] [Tatsuo Miyoshi, Satoru Suzuki] To examine the possibility that outer membrane proteins (OMP) of Synechococcus sp. remain in seawater, we investigated the stability of OMPs in vitro and in situ. Some fractions prepared from Synechococcus sp. CSIRO-94 were treated with trypsin and proteinase K. Four tightly bound OMPs were separated from Synechococcus. We designated the two major OMPs of 52 kDa and 48 kDa as Omp52Sy and Omp48Sy, respectively. Degradation of the OMP in natural seawater was monitored in microcosms to which intact Synechococcus cells and outer membrane (OM) were added. Omp52Sy and Omp48Sy were the most stable against trypsin and proteinase K among the OMPs when they were embedded in the OM. However, in the microcosm experiment using intact cells, Omp52Sy and Omp48Sy were detected in the particulate fraction only during the first 4 days, after which they could not longer be detected. Omp52Sy and Omp48Sy were the most stable proteins among the Synechococcus OMPs in vitro, but they might be degraded in situ. This indicates that stability of Synechococcus porin differs depending on complex formation with other membrane molecules, which might cause different preservation of microbial membrane proteins in the dissolved protein pool in the ocean. This study suggests that Gram negative bacterial OM with thin peptidoglycan forms a lipid bilayer that proptects OMP, but Synechococcus OM with thick peptidoglycan cannot form a lipid bilayer. The incomplete bilayer might not be able to protect from protease attack in the natural environment. The Oceanographic Society of Japan, 2004 Dissolved organic matter (DOM) nationallicence Synechococcus nationallicence outer membrane protein nationallicence porin nationallicence Miyoshi Tatsuo Center for Marine Environmental Studies (CMES), Ehime University, 790-8577, Matsuyama, Japan aut Suzuki Satoru Center for Marine Environmental Studies (CMES), Ehime University, 790-8577, Matsuyama, Japan aut Journal of Oceanography Kluwer Academic Publishers 60/5(2004-10-01), 825-833 0916-8370 60:5<825 2004 60 10872 https://doi.org/10.1007/s10872-005-5775-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10872-005-5775-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Miyoshi Tatsuo Center for Marine Environmental Studies (CMES), Ehime University, 790-8577, Matsuyama, Japan aut NATIONALLICENCE 700 1- Suzuki Satoru Center for Marine Environmental Studies (CMES), Ehime University, 790-8577, Matsuyama, Japan aut NATIONALLICENCE 773 0- Journal of Oceanography Kluwer Academic Publishers 60/5(2004-10-01), 825-833 0916-8370 60:5<825 2004 60 10872 NATIONALLICENCE 856 40 https://doi.org/10.1007/s10872-004-5775-9 text/html Onlinezugriff via DOI Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE NATIONALLICENCE NL-springer