Rev. biol. mar. oceanogr. 51(1): 187-191

Research Note

http://dx.doi.org/10.4067/S0718-19572016000100019

Methylglyoxal metabolism in seaweeds during desiccation

Camila Fierro¹, Camilo López-Cristoffanini², Nicolás Latorre^1,3, Jorge Rivas⁴ and This email address is being protected from spambots. You need JavaScript enabled to view it.^1,5

¹Departamento de Ecología y Biodiversidad, Facultad de Ecología y Recursos Naturales, Universidad Andres Bello, República 440, Santiago, Chile

²Departamento de Biología Vegetal, Facultad de Biología, Universitat de Barcelona, 08028 Barcelona, España

³Programa de Doctorado en Medicina de la Conservación, Facultad de Ecología y Recursos Naturales, Universidad Andres Bello, República 440, Santiago, Chile

⁴Instituto de Ciencias Químicas Aplicadas, Facultad de Ingeniería, Universidad Autónoma de Chile, Llano Subercaseaux 2801, San Miguel, Chile

⁵Center of Applied Ecology & Sustainability (CAPES), Pontificia Universidad Católica de Chile, Avda. Libertador Bernardo O´Higgins 340, Santiago, Chile

  This email address is being protected from spambots. You need JavaScript enabled to view it.

The southwestern Gulf of California has high-value commercial fisheries; however, there are few studies of the taxonomic diversity of fish in this area. Surveys of taxonomic diversity of the fish assemblage at 8 localities near the shore of Bahía de La Paz were undertaken from March 2002 to April 2003. Seasonal changes in diversity of rocky reef fish were analyzed, including taxonomic distance among fish species, using the alpha, alpha average, beta, and gamma diversity indices, the taxonomic distinctness index (TD D*), and the average taxonomic distinctness index (AvTD D+). Submarine visual censuses were carried out along 48 transects measuring 100 × 5 m (500 m2) at 5 m average depth from 09:00-16:00 h. Two seasons were studied: winter with an average temperature of 22.57°C, and summer with an average temperature of 27.09°C. 24,633 fishes, belonging to 92 species and 67 genera were recorded. According to the alpha average, beta, and gamma diversity indices, August had the highest diversity (19.5, 40.5, and 60 species, respectively), and December had the lowest diversity (20.6, 27.4, and 48 species, respectively). Spatial analysis of TD and AvTD were not significantly different, and analysis by season of these indices was not significant different. Greater anthropogenic impact would cause differences in TD and AvTD found at El Guano compared with other locations.

In primary producers, diverse stressors cause an over-production of methylglyoxal (MG), which is principally detoxified by glyoxalase I (GLO1) activity. A recent proteomic study found that GLO1 was up-regulated during natural desiccation in the red seaweed Pyropia orbicularis, which inhabits the upper intertidal rocky zone and compared to other species, is highly tolerant to air exposure. To better understand and determine differential responses to desiccation stress, this study evaluated MG concentration and GLO1 activity in two species with contrasted vertical distribution, P. orbicularis and Lessonia spicata (lower distribution). Results showed that P. orbicularis successfully scavenges MG via increased GLO1 activity during desiccation. In contrast, GLO1 activity in L. spicata did not increase during desiccation, resulting in MG overproduction. This study is the first to quantify MG and GLO1 levels in seaweeds during natural stress, and partly explain the mechanisms by which P. orbicularis is dominant in the upper rocky intertidal zone.

Key words: Methylglyoxal, glyoxylase I, Pyropia, Lessonia, desiccation