Martins Inês, Romão Célia V, Goulart Joana, Cerqueira Teresa, Santos Ricardo S, Bettencourt Raul
MARE - Marine and Environmental Sciences Centre, University of Azores, 9901-862 Horta, Portugal; IMAR/Department of Oceanography and Fisheries, University of Azores, 9901-862 Horta, Portugal.
Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Avenida da República (EAN), 2780-157 Oeiras, Portugal.
Mar Environ Res. 2016 Mar;114:65-73. doi: 10.1016/j.marenvres.2016.01.003. Epub 2016 Jan 11.
Deep sea hydrothermal Bathymodiolus azoricus mussels from Portuguese EEZ Menez Gwen hydrothermal field possess the remarkable ability to overcome decompression and survive successfully at atmospheric pressure conditions. We investigated the potential use of antioxidant defense enzymes in mussel B. azoricus as biomarkers of oxidative stress induced by long term acclimatization to atmospheric pressure conditions. Mussels collected at Menez Gwen hydrothermal field were acclimatized for two weeks in three distinct conditions suitable of promoting physiological stress, (i) in plain seawater for concomitant endosymbiont bacteria loss, (ii) in plain seawater under metal iron exposure, (iii) constant bubbling methane and pumped sulfide for endosymbiont bacteria survival. The enzymatic activities of superoxide dismutase (SOD), catalase (CAT), and iron storage proteins in addition to electrophoretic profiles were examined in vent mussel gills and digestive gland. Gills showed approximately 3 times more SOD specific activity than digestive glands. On the other hand, digestive glands showed approximately 6 times more CAT specific activity than gills. Iron storage proteins were identified in gill extracts from all experimental conditions mussels. However, in digestive gland extracts only fresh collected mussels and after 2 weeks in FeSO4 showed the presence of iron storage proteins. The differences between SOD, CAT specific activities and the presence of iron storage proteins in the examined tissues reflect dissimilar metabolic and antioxidant activities, as a result of tissue specificities and acclimatization conditions influences on the organism.
来自葡萄牙专属经济区梅内斯格温热液区的深海热液阿佐里深水贻贝具有非凡的能力，能够克服减压并在常压条件下成功存活。我们研究了贻贝阿佐里深水贻贝中抗氧化防御酶作为长期适应常压条件所诱导的氧化应激生物标志物的潜在用途。在梅内斯格温热液区采集的贻贝在三种不同的适合促进生理应激的条件下进行了两周的驯化，（i）在普通海水中以伴随共生细菌损失，（ii）在普通海水中暴露于金属铁，（iii）持续鼓泡甲烷和泵送硫化物以维持共生细菌存活。在贻贝鳃和消化腺中检测了超氧化物歧化酶（SOD）、过氧化氢酶（CAT）的酶活性以及铁储存蛋白，并分析了电泳图谱。鳃的SOD比活性大约是消化腺的3倍。另一方面，消化腺的CAT比活性大约是鳃的6倍。在所有实验条件下的贻贝鳃提取物中都鉴定出了铁储存蛋白。然而，在消化腺提取物中，只有新鲜采集的贻贝以及在硫酸亚铁中放置2周后的贻贝显示出铁储存蛋白的存在。在所检查组织中SOD、CAT比活性以及铁储存蛋白存在情况的差异反映了由于组织特异性和驯化条件对生物体的影响而导致的不同代谢和抗氧化活性。
