Limits...
Seasonal Changes in Mycosporine-Like Amino Acid Production Rate with Respect to Natural Phytoplankton Species Composition.

Ha SY, Lee Y, Kim MS, Kumar KS, Shin KH - Mar Drugs (2015)

Bottom Line: The dominance of diatoms indicated that they had a long-term response to UVR.Our results demonstrate that both the net production rate as well as the concentration of MAAs related to photoinduction depended on the phytoplankton community structure.In addition, seasonal changes in UVR also influenced the quantity and production of MAAs in phytoplanktons (especially Cyanophyceae).

View Article: PubMed Central - PubMed

Affiliation: Division of Polar Ocean Environment, Korea Polar Research Institute (KOPRI), 26 Songdomirae-ro, Yeonsu-gu, Incheon 406-840, Korea. syha@kopri.re.kr.

ABSTRACT
After in situ incubation at the site for a year, phytoplanktons in surface water were exposed to natural light in temperate lakes (every month); thereafter, the net production rate of photoprotective compounds (mycosporine-like amino acids, MAAs) was calculated using (13)C labeled tracer. This is the first report describing seasonal variation in the net production rate of individual MAAs in temperate lakes using a compound-specific stable isotope method. In the mid-latitude region of the Korean Peninsula, UV radiation (UVR) usually peaks from July to August. In Lake Paldang and Lake Cheongpyeong, diatoms dominated among the phytoplankton throughout the year. The relative abundance of Cyanophyceae (Anabaena spiroides) reached over 80% during July in Lake Cheongpyeong. Changes in phytoplankton abundance indicate that the phytoplankton community structure is influenced by seasonal changes in the net production rate and concentration of MAAs. Notably, particulate organic matter (POM) showed a remarkable change based on the UV intensity occurring during that period; this was because of the fact that cyanobacteria that are highly sensitive to UV irradiance dominated the community. POM cultured in Lake Paldang had the greatest shinorine (SH) production rate during October, i.e., 83.83 ± 10.47 fgC·L(-1)·h(-1). The dominance of diatoms indicated that they had a long-term response to UVR. Evaluation of POM cultured in Lake Cheongpyeong revealed that there was an increase in the net MAA production in July (when UVR reached the maximum); a substantial amount of SH, i.e., 17.62 ± 18.34 fgC·L(-1)·h(-1), was recorded during this period. Our results demonstrate that both the net production rate as well as the concentration of MAAs related to photoinduction depended on the phytoplankton community structure. In addition, seasonal changes in UVR also influenced the quantity and production of MAAs in phytoplanktons (especially Cyanophyceae).

Show MeSH
Individual MAAs production rate in (a) Lake Paldang and (b) Lake Cheongpyeong. PA: exposed to PAR+UV-A; PAB: exposed to PAR+UV-A+UV-B; SH: Shinorine (black bars); PA: Palythine (gray bars); MG: Mycosporine-glycine (light gray bars).
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4663551&req=5

marinedrugs-13-06740-f002: Individual MAAs production rate in (a) Lake Paldang and (b) Lake Cheongpyeong. PA: exposed to PAR+UV-A; PAB: exposed to PAR+UV-A+UV-B; SH: Shinorine (black bars); PA: Palythine (gray bars); MG: Mycosporine-glycine (light gray bars).

Mentions: Irrespective of exposure to UVR, the highest MAA net production rates were observed from POM in Lake Paldang during October. Notably, the POM exhibited maximum net production rate even when UVR was cut off. Here, the concentrations of SH, PA and MG were 83.83 ± 10.47, 30.18 ± 11.2 and 33.26 ± 2.01 fgC·L−1·h−1, respectively. Particularly, the POM exposed to UVR during October demonstrated SH, PA and MG of 11.82 ± 0.01, 3.19 ± 0.3 and 4.02 ± 0.22 fgC·L−1·h−1, respectively. Based on these observations, it could be stated that the net production rates of UV-exposed phytoplankton were higher than those of the phytoplankton not exposed to UV (Figure 2). During all months, except October, the POM exhibited very low productivity; moreover, in July and November, slightly higher productivity rates were observed for the POM.


Seasonal Changes in Mycosporine-Like Amino Acid Production Rate with Respect to Natural Phytoplankton Species Composition.

Ha SY, Lee Y, Kim MS, Kumar KS, Shin KH - Mar Drugs (2015)

Individual MAAs production rate in (a) Lake Paldang and (b) Lake Cheongpyeong. PA: exposed to PAR+UV-A; PAB: exposed to PAR+UV-A+UV-B; SH: Shinorine (black bars); PA: Palythine (gray bars); MG: Mycosporine-glycine (light gray bars).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4663551&req=5

marinedrugs-13-06740-f002: Individual MAAs production rate in (a) Lake Paldang and (b) Lake Cheongpyeong. PA: exposed to PAR+UV-A; PAB: exposed to PAR+UV-A+UV-B; SH: Shinorine (black bars); PA: Palythine (gray bars); MG: Mycosporine-glycine (light gray bars).
Mentions: Irrespective of exposure to UVR, the highest MAA net production rates were observed from POM in Lake Paldang during October. Notably, the POM exhibited maximum net production rate even when UVR was cut off. Here, the concentrations of SH, PA and MG were 83.83 ± 10.47, 30.18 ± 11.2 and 33.26 ± 2.01 fgC·L−1·h−1, respectively. Particularly, the POM exposed to UVR during October demonstrated SH, PA and MG of 11.82 ± 0.01, 3.19 ± 0.3 and 4.02 ± 0.22 fgC·L−1·h−1, respectively. Based on these observations, it could be stated that the net production rates of UV-exposed phytoplankton were higher than those of the phytoplankton not exposed to UV (Figure 2). During all months, except October, the POM exhibited very low productivity; moreover, in July and November, slightly higher productivity rates were observed for the POM.

Bottom Line: The dominance of diatoms indicated that they had a long-term response to UVR.Our results demonstrate that both the net production rate as well as the concentration of MAAs related to photoinduction depended on the phytoplankton community structure.In addition, seasonal changes in UVR also influenced the quantity and production of MAAs in phytoplanktons (especially Cyanophyceae).

View Article: PubMed Central - PubMed

Affiliation: Division of Polar Ocean Environment, Korea Polar Research Institute (KOPRI), 26 Songdomirae-ro, Yeonsu-gu, Incheon 406-840, Korea. syha@kopri.re.kr.

ABSTRACT
After in situ incubation at the site for a year, phytoplanktons in surface water were exposed to natural light in temperate lakes (every month); thereafter, the net production rate of photoprotective compounds (mycosporine-like amino acids, MAAs) was calculated using (13)C labeled tracer. This is the first report describing seasonal variation in the net production rate of individual MAAs in temperate lakes using a compound-specific stable isotope method. In the mid-latitude region of the Korean Peninsula, UV radiation (UVR) usually peaks from July to August. In Lake Paldang and Lake Cheongpyeong, diatoms dominated among the phytoplankton throughout the year. The relative abundance of Cyanophyceae (Anabaena spiroides) reached over 80% during July in Lake Cheongpyeong. Changes in phytoplankton abundance indicate that the phytoplankton community structure is influenced by seasonal changes in the net production rate and concentration of MAAs. Notably, particulate organic matter (POM) showed a remarkable change based on the UV intensity occurring during that period; this was because of the fact that cyanobacteria that are highly sensitive to UV irradiance dominated the community. POM cultured in Lake Paldang had the greatest shinorine (SH) production rate during October, i.e., 83.83 ± 10.47 fgC·L(-1)·h(-1). The dominance of diatoms indicated that they had a long-term response to UVR. Evaluation of POM cultured in Lake Cheongpyeong revealed that there was an increase in the net MAA production in July (when UVR reached the maximum); a substantial amount of SH, i.e., 17.62 ± 18.34 fgC·L(-1)·h(-1), was recorded during this period. Our results demonstrate that both the net production rate as well as the concentration of MAAs related to photoinduction depended on the phytoplankton community structure. In addition, seasonal changes in UVR also influenced the quantity and production of MAAs in phytoplanktons (especially Cyanophyceae).

Show MeSH