Special Issue "Marine Photoprotective Compounds"

Guest Editor
Dr. Manfred Klisch
Plant Ecophysiology, Department of Biology, Friedrich-Alexander University, Erlangen, Germany
E-Mail:
Interests: ecophysiology of algae and cyanobacteria; biochemical adaptations to environmental stress

Dear Colleagues,

Marine organisms of the photic zone have evolved a variety of defense strategies against the adverse effects of solar radiation. These include screening of the ultraviolet proportions of the solar spectrum, quenching of photochemically generated radicals and repair of photodamage. Apart from carotenoids the mycosporine-like amino acids (MAAs) are among the most prominent examples of marine photoprotective compounds. These strong UV-absorbers have gained continuing scientific attention over the last decades. The increasing public concern regarding possible adverse effects of synthetic sunscreens underlines the necessity of natural alternatives and adjuvants. Therefore MAAs have attained particular commercial interest in the recent years. The current special issue will present a selection of research papers and reviews on the different aspects of marine photoprotective compounds. These can be original research articles as well as review papers related to marine photoprotective compounds. The focus of the papers may range from physiological and biochemical aspects to possible applications.

Manfred Klisch, Ph. D.
Guest Editor

Submission

All papers should be submitted to marinedrugs@mdpi.org with copy to the Editors. To be published continuously until the deadline and papers will be listed together at the special websites. Both, research articles and review articles are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editors for announcment on this website.

Submitted papers should not have been published previously, nor be under consideration for publication elsewhere. All papers are refereed through a peer-review process. A guide for authors, sample copies and other relevant information for submitting papers are available on the Instructions for Authors page. Marine Drugs is an international peer-reviewed quarterly journal published by Molecular Diversity Preservation International.

Please visit the Instructions for Authors page before submitting a paper Open Access publication fees are 1000 CHF per paper. English correction fees (250 CHF) will be added in certain cases (1250 CHF per paper for those papers that require extensive additional formatting and/or English corrections.).

• carotenoids
• mycosporine-like amino acids
• scytonemin; photoprotective compounds
• ultraviolet radiation
• reactive oxygen species

Type of Paper: Review
Title: De-Epoxidated Xanthophylls and Mycosporine-Like Amino Acids as Thermal Energy Dissipators of Excess of Light in Algae: Capacity for UVR Photoprotection
Authors: Nathalie Korbee and Félix L. Figueroa
Affiliation: Departamento de Ecología, Facultad de Ciencias, Campus Universitario de Teatinos s/n, Universidad de Málaga, 29071 Málaga, Spain; E-Mail: nkorbee@uma.es (N.K.)
Abstract: Xanthophyll cycle is known to contribute to photoprotection of excess light by thermal dissipation of excess absorbed energy. The two most common classes of xanthophyll cycle pigments are the diadinoxanthin-diatoxanthin cycle and the violaxanthin-antheraxanthin-zeaxanthin cycle pigments. This cycle is present in different photosynthetic organisms such as Chlorophyceae, Prasinophyceae, Haptophyceae, Dinophyceae, Bacillariophyceae. Although non active xanthophyll cycle has been found in Rhodophyceae, Cryptophyceae, Cyanophyta and Prochlorophytes, some de-epoxidized xanthophylls are present. Research on the effect of UV radiation (UVR) exposure on xanthophyll cycle activity has produced contrasting views; thus the UVR photoprotective capacity of this cycle is not clear. By other hand, most algae groups synthesize mycosporine-like amino acids as an effective UVR sunscreen compound that absorbs harmful UVR and emits heat to prevent photodamage and also as an antioxidant compound. Therefore, several species show both photoprotection strategies but depending on environmental factors (irradiance, nutrient, temperature) they could use more effectively one of them. The current contribution summarizes the state-of art on photoprotection mediated by both xanthophyll cycle and mycosporine-like amino acids in algae putting special emphasis on the positive or negative synergistic interaction among different environmental factors.

Type of Paper: Review
Title: Mycosporine-like amino acids: Relevant secondary metabolites from marine organisms. Chemical and ecological aspects
Authors: José I. Carreto * and Mario O. Carignan
Affiliation: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), PaseoVictoria Ocampo N°1, Escollera Norte, B7602HSA, Mar del Plata, Argentina. E-Mails: jcarreto@inidep.edu.ar ; marioc@inidep.edu.ar
* Author to whom correspondence should be addressed, E-Mail: jcarreto@inidep.edu.ar; Tel.: +54-223-4862586; Fax: +54-223-4861831
Abstract: Taxonomically diverse marine and terrestrial organisms have evolved the capacity to synthesize, accumulate and metabolize a variety of UV-absorbing substances called mycosporine-like amino acids (MAAs) as part of an overall strategy to diminish the direct and indirect damaging effects of environmental UVR. Whereas the enzymatic machinery to synthesize MAAs was probably inherited from cyanobacteria ancestors via the endosymbiont hypothesis, metazoans lack this biochemical pathway, but can acquire and metabolize these compounds by tropic transference, symbiotic or bacterial association. In this review we describe the structure and physicochemical properties of MAAs, including the recently discovered compounds and the modern methods used for their isolation and identification updating previous reviews. On this basis, we review the metabolism and distribution of this unique class of metabolites among marine organism.
Keywords: mycosporine-like amino acids; physicochemical properties; isolation; distribution; metabolism

Type of Paper: Article
Title: Distribution and Abundance of MAAs in 13 Classes and 33 Species of Microalgae
Authors: Carole Anne Llewellyn and Ruth Airs
Affiliation: Plymouth Marine Laboratory, Prospect Place, The Hoe, Plymouth Pl1-3Dh, UK; E-Mails: call@pml.ac.uk (C.A.L.); ruai@pml.ac.uk (R.A.)
Abstract: We provide a direct comparison of the distribution and abundance of mycosporine-like amino acids (MAAs) in a diverse range of microalgal cultures (33 species across 13 classes) grown without supplementary ultraviolet radiation. Usijerene, palythene, palythine, mycosporine-glycine, palythenic acid, porphyra-334 and shinorine in addition to a further 17 UV-absorbing compounds including two with multiple absorption maxima ( max) were monitored. MAAs were abundant (up to 7 pg MAA cell-1) in 10 species with more minor and often unknown MAAs in a further 11 cultures. Shinorine was the most frequently occurring and abundant MAA (up to 6.5 pg cell-1) and was present in all but two of the MAA containing species. Our results give improved insight into the diversity and abundance of MAAs, important from an ecological perspective and as a guide for applied researchers seeking cultures containing particular UV screening properties.