This study is aimed at assessing the effects of multiple stressors (thermal shock, fishing capture, and exposure to air) on the benthic stomatopod Squilla mantis, a burrowing crustacean quite widespread in the Mediterranean Sea. Laboratory analyses were carried out to explore the physiological impairment onset over time, based on emersion and thermal shocks, on farmed individuals. Parallel field-based studies were carried out to also investigate the role of fishing (i.e., otter trawling) in inducing physiological imbalance in different seasonal conditions. The dynamics of physiological recovery from physiological disruption were also studied. Physiological stress was assessed by analysing hemolymph metabolites (L-Lactate, D-glucose, ammonia, and H+), as well as glycogen concentration in muscle tissues. The experiments were carried out according to a factorial scheme considering the three factors (thermal shock, fishing capture, and exposure to air) at two fixed levels in order to explore possible synergistic, additive, or antagonistic effects among factors. Additive effects on physiological parameters were mainly detected when the three factors interacted together while synergistic effects were found as effect of the combination of two factors. This finding highlights that the physiological adaptive and maladaptive processes induced by the stressors result in a dynamic response that may encounter physiological limits when high stress levels are sustained. Thus, a further increase in the physiological parameters due to synergies cannot be reached. Moreover, when critical limits are encountered, mortality occurs and physiological parameters reflect the response of the last survivors. In the light of our mortality studies, thermal shock and exposure to air have the main effect on the survival of S. mantis only on trawled individuals, while lab-farmed individuals did not show any mortality during exposure to air until after 2 hours.
Hemocyanins are giant oxygen transport proteins of molluscs and arthropods, which display high\ud cooperativity and a complex pattern of conformations, generated by hierarchical allosteric interactions\ud of their complex quaternary structure. A still unanswered question is the correlation between the\ud functional properties of the postulated conformers and structural features that govern their oxygen\ud binding, such as metal complex coordination. In this study we focus on the dodecameric hemocyanin of\ud the crustacean Carcinus aestuarii, with the aim to obtain a functional and structural characterization of\ud the individual conformational states giving rise to cooperativity, by entrapping hemocyanin into a sol–gel\ud matrix. The latter has attracted much attention as an ideal substrate for immobilization of\ud macromolecules within the pores of a hydrated and optically transparent matrix that preserves the\ud structures and functionalities of the encapsulated macromolecules. In our experimental approach, the\ud sol–gel is capable of blocking the conformational transitions of the hemocyanin induced by changing\ud the oxygen concentration in solution studies. This enables characterization of both the oxygenated and\ud deoxygenated forms of particular conformers. Here we describe the oxygen binding properties of\ud individual matrix entrapped conformers of C. aestuarii hemocyanins and the spectroscopic features\ud characteristic for these conformations. Since the quaternary structure itself is not altered, as the SANS\ud data unambiguously show in the sol–gel a dodecameric organization for C. aestuarii hemocyanin, we\ud propose that the entrapment of hemocyanin in a sol–gel is able to freeze functionally relevant\ud conformational distributions under appropriate conditions. The spectroscopic characterization of the\ud functionally characterized conformers trapped in the sol gel allowed us to assign the differences in the\ud active site geometry as observed by XAS to individual conformations
No abstract
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.