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Spatial and temporal variations in free polyamine distributions in Uranouchi Inlet, Japan 总被引:1,自引:0,他引:1
Naoyoshi Nishibori Yukihiko Matuyama Takushi Uchida Takamitu Moriyama Yoshihiko Ogita Masumi Oda Hitoshi Hirota 《Marine Chemistry》2003,82(3-4):307-314
Polyamines are an essential component of living organisms that influence normal cell growth and development. Despite the possible importance of polyamines for marine microbial ecology, concentrations of polyamines in seawater are not well known.Using HPLC analysis with a cation exchange column and OPA reagent, we determined polyamine concentrations in seawater without carrying out desalting, concentration or derivatization steps prior to chromatography.In seawater collected from Uranouchi Inlet, putrescine and spermidine were the predominant polyamines, ranging from undetectable (N.D.) to 4.4 nM and N.D. to 2.8 nM, respectively. Though other polyamines were detected, the frequency of detection was much lower than that of putrescine and spermidine; concentrations ranged from N.D. to 0.9 nM for cadaverine, and N.D. to 3.2 nM for norspermidine. Norspermine and spermine were detected in only a few samples; their concentrations varied from N.D. to 3.2 nM and N.D. to 0.5 nM, respectively. These concentrations were higher in the summer. 相似文献
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Seok Jin Oh Yang Ho Yoon Tamiji Yamamoto Yukihiko Matsuyama 《Ocean Science Journal》2005,40(4):183-190
We investigated the seasonal variability of free alkaline phosphatase activity in seawater and alkaline phosphatase hydrolysable
phosphorus (APHP) at 3 stations in Hiroshima Bay using alkaline phosphatase extracted from the dinoflagellates Alexandrium
tamarense and Gymnodinium catenatum. The dissolved inorganic phosphorus (DIP) was lower than 1 μM in all samples; the lowest
values were in May. The amount of APHP was high at the surface and bottom waters of all stations in May, showing DIP-depleted
conditions. In August and November, the amount of APHP was much less than the amount of APHP in May, indicating that the availability
of dissolved organic phosphorus (DOP) for these species was low and/or uptake during the dinoflagellate blooming might have
occurred in the area. The results obtained from short-term variations of AP activity might suggest that the growth of dinoflagellates
in this season may be partly supported by the AP produced by other diatoms. 相似文献
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Yasuhiro Yamasaki Yanan Zou Jyoji Go Tomoyuki Shikata Yukihiko Matsuyama Kiyohito Nagai Yohei Shimasaki Kenichi Yamaguchi Yuji Oshima Tatsuya Oda Tsuneo Honjo 《Journal of Sea Research》2011,65(1):76-83
We used bi-algal culture experiments to investigate and verify the roles of growth interaction between Heterocapsa circularisquama and Prorocentrum dentatum in monospecific bloom formation. Growth of H. circularisquama was slightly inhibited when inoculated at 102 cells mL–1 along with P. dentatum at 104 cells mL–1. In other combinations of inoculation densities, P. dentatum density rapidly decreased to extremely low levels in the presence of H. circularisquama. We used a mathematical model to simulate growth and interactions of H. circularisquama and P. dentatum in bi-algal cultures. The model indicates that one species will always inhibit the growth of the other and that the relative initial cell densities of the species are critical in determining the outcome. When cultured together under conditions without cell contact, growth of H. circularisquama and P. dentatum was not inhibited. As with P. dentatum, the growth of Heterosigma akashiwo and Skeletonema costatum was inhibited in intact cell suspensions with H. circularisquama, but a nontoxic species, Heterocapsa triquetra, did not affect the growth of P. dentatum or the other species. Similarly, cell suspensions of H. circularisquama showed hemolytic activity toward rabbit erythrocytes, but those of H. triquetra did not. In addition, the cell-free supernatant of H. circularisquama cultures showed no significant hemolytic activity. These results suggest that H. circularisquama causes lethality in P. dentatum by direct cell contact in which live-cell-mediated hemolytic activity might be a contributing factor. 相似文献
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Minoru Wada Yukiko Takano Saki Nagae Yuka Ohtake Yu Umezawa Shinichi Nakamura Makoto Yoshida Yukihiko Matsuyama Mitsunori Iwataki Satoshi Takeshita Tatsuya Oda 《Journal of Oceanography》2018,74(6):587-593
Acute and severe hypoxia associated with harmful algal bloom has become one of the major causes for the environmental deterioration of coastal areas. Although it is generally thought that a large part of the dissolved oxygen consumption at a bloom site is initiated by heterotrophic bacteria that attack organic matter derived from dead or dying algal cells, precise microbial processes leading to the hypoxia are yet to be examined. Here we show temporal dynamics of extracellular dissolved organic carbon (DOC) of the red tide forming raphidophyte Chattonella marina and bacterial populations associating with the algae under laboratory conditions. During the growth of non-axenic strains of C. marina, we monitored abundance of algae, associated bacteria, and DOC in the culture media. Bacterial cell abundance increased in response to the increase in DOC both at the beginning and the late log phase of the algal growth. Flow cytometric analysis revealed that transient increase in the percentage of respiratory-active bacterial cells also coincided with the timing of the increase in bacterial abundance and DOC. These results strongly suggest that DOC released from growing C. marina fuels respiration and growth of planktonic bacteria surrounding the algae. This has implications for the role of DOC released from C. marina bloom before the collapse in mediating interactions between neighboring algae and bacterial assemblage which may eventually lead to algal bloom-associated hypoxia. 相似文献
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