Marine Life Science & Technology最新文献

Kelps are pivotal to temperate coastal ecosystems, providing essential habitat and nutrients for diverse marine life, and significantly enhancing local biodiversity. The impacts of elevated CO₂ levels on kelps may induce far-reaching effects throughout the marine food web, with potential consequences for biodiversity and ecosystem functions. This study considers the kelp Macrocystis pyrifera and its symbiotic microorganisms as a holistic functional unit (holobiont) to examine their collective response to heightened CO₂ levels. Over a 4 month cultivation from the fertilization of M. pyrifera gametes to the development of juvenile sporophytes, our findings reveal that elevated CO₂ levels influence the structure of the M. pyrifera symbiotic microbiome, alter metabolic profiles, and reshape microbe-metabolite interactions using 16S rRNA amplicon sequencing and liquid chromatography coupled to mass spectrometry analysis. Notably, Dinoroseobacter, Sulfitobacter, Methylotenera, Hyphomonas, Milano-WF1B-44 and Methylophaga were selected as microbiome biomarkers, which showed significant increases in comparative abundance with elevated CO₂ levels. Stress-response molecules including fatty-acid metabolites, oxylipins, and hormone-like compounds such as methyl jasmonate and prostaglandin F2a emerged as critical metabolomic indicators. We propose that elevated CO₂ puts certain stress on the M. pyrifera holobiont, prompting the release of these stress-response molecules. Moreover, these molecules may aid the kelp's adaptation by modulating the microbial community structure, particularly influencing potential pathogenic bacteria, to cope with environmental change. These results will enrich the baseline data related to the chemical interactions between the microbiota and M. pyrifera and provide clues for predicting the resilience of kelps to future climate change.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-024-00259-5.

Understanding the potential areas suitable for offshore mariculture is crucial to global seafood security. Here, we map the potential global offshore mariculture areas for 23 principal commercial finfish using an ensemble model. The model involves the temporal-spatial heterogeneity of environments and constraints of temperature-dependent hypoxia and cold edges of cultured finfish by metabolic index and lower thermal safety margin, respectively. Our results show that currently, there is 9.16 ± 1.22 million km² of potentially suitable area for offshore finfish mariculture. Under climate change, the potential suitable area will be reduced to between 86.7% and 91.7% of the current size by 2050. Compared to the decline in tropical regions, the expanded potential areas in temperate and polar regions will become more important for global seafood security. The potential offshore finfish mariculture area responds differently to global change among species, and cold-water finfish may benefit from global warming. Overall, despite changes in the distribution of global offshore mariculture areas and replacements of local potential mariculture species, offshore finfish mariculture still holds immense potential in the future.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-024-00257-7.

The genus Callistoctopus comprises 13 species, and has been reported mostly in the Western Pacific Ocean. Here, we described three new species from China, Ca. paucilamellus sp. nov., Ca. sparsus sp. nov., and Ca. gracilis sp. nov., based on morphometric and meristic characteristics. The diagnoses, descriptions and detailed morphometric data are provided for each species. The cytochrome c oxidase I (COI) genes of the three new species are sequenced, and compared with related species and analyzed for their systematic positions. Both phylogenetic trees constructed using three mitochondrial genes (12S rRNA, 16S rRNA, COI) and one nuclear gene (Rhodopsin) revealed that our new species formed into two distinct clades with strong support values. One clade included Ca. gracilis sp. nov., Ca. sp. 1, Ca. xiaohongxu, Ca. tenuipes and Ca. paucilamellus sp. nov., which clustered together. The other clade showed that Ca. sparsus sp. nov. was closely related to Ca. sp. 2 and Ca. sp. 3. Ca. luteus and Ca. macropus were located at the base of the Callistoctopus group. Based on our integrative studies, both morphological and molecular evidence suggested strongly that O. minor is more likely to be classified as a species of Callistoctopus. Morphological comparisons were made between the three new species and related taxa, which could be recognized based on the 7-8 gill lamellae of each demibranch, numerous small black spots on the subdermal layer of the arms, and an elongated body.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-024-00258-6.

Bacterial community play an essential role in regulating water quality and the global biogeochemical cycle in aquatic ecosystems. However, how trophic interactions (i.e., biotic factors) regulate the diversity and composition of bacterial community in lake ecosystems remains unknown. Here, we employed DNA meta-barcoding of water samples to explore the impact of bacterivorous protozoans on the bacterial community. The results showed significant seasonal variations in the diversity and composition of both bacterial and protist communities. The composition of bacterivorous protozoans was identified as the primary predictor for the bacterial community alpha diversity in spring and summer, and for beta diversity in spring and autumn, indicating that biotic interactions play a greater role in driving the diversity of bacterial community across different seasons. Biological factors were more important than environmental factors for explaining the variations in the relative abundance of several bacterial genera (i.e., Pseudoxanthomonas, hgcI_clade, and Pseudorhodobacter). Network analyses showed that bacterial networks differed among seasons, and the autumn network exhibited the highest stability. Our findings indicated that the bacterial community stability was significantly affected by environmental factors, specifically SO₄ ^2-and PO₄ ^3-, rather than bacterivorous protozoans. Overall, our findings provide new perspectives on the role of trophic interactions in maintaining the structure of bacterial community in different seasons, and enhance our understanding of the bacterial community assembly in lake ecosystems.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-024-00256-8.

Obesity has become a worldwide health problem. Seeking natural products with anti-obesity activity from lots of fungi has drawn the attention of pharmacologists. In our study, dipenipenoids A and B (1 and 2), the first dimeric indole-diterpenoids with a rare C-20-C-22' linkage, and their monomers (3 and 4), were isolated from a marine-derived Penicillium sp. CF-06 fungus from Suaeda salsa. The absolute configurations of 1-3 were assigned by the calculated TDDFT ECD method. The structure of 4 was verified by a single-crystal X-ray diffraction method for the first time. Interestingly, 1 and 2 displayed significant effects on the differentiation of 3T3-L1 adipocytes by down-regulating the expression of peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer binding protein alpha (C/EBPα) proteins, while monomers 3 and 4 exhibited no activity. Molecular docking results explained the mechanism that the interaction between dimer 1 and PPARγ was stronger than that between monomer 3 and PPARγ. Our research could provide new insight for the discovery of anti-obesity drugs.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-024-00253-x.

Estuaries are usually characterized by strong spatial and temporal variability in water physicochemical conditions and are often largely affected by human activities. One important source of variability is caused by tides that can swiftly alter not only physicochemical conditions but also the abundance and composition of the biota. The effect of the diurnal tidal cycle on microbial community composition during different seasons remains uncertain, although this knowledge underlies having effective monitoring programs for water quality and potential identification of health risk conditions. In this study, we assessed the bacterioplankton community composition and diversity across four tidal water levels in a tropical estuary characterized by a mixed semidiurnal tide regime (i.e., two high and two low tides of varying amplitudes) during both dry and wet seasons. The bacterial community composition varied significantly among the four tidal levels, but only during the dry season, when the influence of the seawater intrusion was largest. Bacterial indicators' taxa identified using the Indicator Value Index were found within Cyanobacteria, Actinobacteriota, Bacteroidota, and Proteobacteria. The indicator taxon Cyanobium sp. had a prominent presence across multiple tidal levels. The main predicted phenotypes of the bacterial communities were associated with potential pathogenicity, gram-negative, and biofilm formation traits. While there were no marked predicted phenotypic differences between seasons, pathogenic and gram-negative traits were more prevalent in the dry season, while biofilm formation traits dominated in the wet season. Overall, our findings underscore the intricate relationship between river hydrodynamics and bacterial composition variability and hint a significant human impact on the water quality of the Bangpakong River.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-024-00254-w.

Fisheries are social-ecological systems. Evaluating the sustainability of fisheries requires methods to measure performance from ecological, economic, social, and governance aspects. Whereas a number of multi-dimensional evaluation tools such as fishery performance indicators (FPIs) have been used for assessing fishery management systems, fishery management practices and data availability are likely to differ substantially among fisheries in different countries. This makes it at least somewhat problematic to precisely adapt this methodology to fisheries within a given country. This study constructed a practical tool to evaluate and compare fishery systems in China. On the basis of an established indicator library and the FPIs tool, indicators in the newly developed tool for comprehensive fisheries evaluation were selected according to the management objectives, data availability, and the authority of relevant indicators. The sustainability assessment tool for Chinese fisheries (SAT-fish) provides a three-tier hierarchical framework covering 60 indicators, of which 48 indicators were extracted from the FPIs tool and 12 indicators were associated with policy statements. Applicability and comprehensiveness of this tool in comparison with six other well-established frameworks were investigated. This tool offers a promising new method to assess the sustainability of fishery systems in China, with great potential to guide Chinese fisheries towards a higher level of sustainability.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-024-00251-z.

Genomic selection (GS) applied to the breeding of aquatic animals has been of great interest in recent years due to its higher accuracy and faster genetic progress than pedigree-based methods. The genetic analysis of complex traits in GS does not escape the current excitement around artificial intelligence, including a renewed interest in deep learning (DL), such as deep neural networks (DNNs), convolutional neural networks (CNNs), and autoencoders. This article reviews the current status and potential of DL applications in phenotyping, genotyping and genomic estimated breeding value (GEBV) prediction of GS. It can be seen from this article that CNNs obtain phenotype data of aquatic animals efficiently, and without injury; DNNs as single nucleotide polymorphism (SNP) variant callers are critical to have shown higher accuracy in assessments of genotyping for the next-generation sequencing (NGS); autoencoder-based genotype imputation approaches are capable of highly accurate genotype imputation by encoding complex genotype relationships in easily portable inference models; sparse DNNs capture nonlinear relationships among genes to improve the accuracy of GEBV prediction for aquatic animals. Furthermore, future directions of DL in aquaculture are also discussed, which should expand the application to more aquaculture species. We believe that DL will be applied increasingly to molecular breeding of aquatic animals in the future.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-024-00252-y.

Determining and comparing mitochondrial genomes (mitogenomes) are essential for assessing the diversity and evolution of mitochondria. Ciliates are ancient and diverse unicellular eukaryotes, and thus are ideal models for elucidating the early evolution of mitochondria. Here, we report on six new mitogenomes of spirotrichs, a dominant ciliate group, and perform comparative analyses on 12 representative species. We show that: (1) the mitogenomes of spirotrichs are linear structures with high A+T contents (61.12-81.16%), bidirectional transcription, and extensive synteny (except for the nad5, ccmf and cob genes in Euplotia); (2) the non-split of NADH dehydrogenase subunit 2 gene (nad2) is a plesiomorphy of ciliates, whereas it has evolved into a split gene in Spirotrichea (apart from Euplotes taxa), Oligohymenophorea, and Armophorea; (3) the number of small subunit ribosomal proteins (rps) encoded in mitogenomes increases in the later branching classes of ciliates, whereas rps8 shows a loss trend during the evolution of Euplotes taxa; (4) the mitogenomes of spirotrichs exhibit A/T codon bias at the third position, and the codon bias is mainly due to DNA mutation in oligotrichs, hypotrichs and Diophrys appendiculata; (5) the phylogenetic position of D. appendiculata is unstable and controversial based on both phylogenetic analyses and mitogenome evidence. In summary, we investigated the mitogenome diversity of spirotrichs and broadened our understanding of the evolution of mitochondria in ciliates.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-024-00249-7.

Aquaculture is critical to reduce protein deficiencies and supplement the world's demand for seafood. However, the culture environment predisposes farmed animals to infectious diseases. In particular, the high density of fish, crustacean, mollusk, sea cucumber or algal species allows for the rapid spread of infectious diseases resulting in devastating losses. Massive amounts of antibiotics have been used to sustain aquaculture production. This has led to the critical need to evaluate the impact of current control measures and optimize disease management schemes with an emphasis on global impact and sustainability. Furthermore, local and global changes have enhanced the pathogens' effects over aquaculture settings because increased temperature and pollution may trigger virulence genes and toxin production. Technological developments including biofloc technology, integrated multitrophic systems, recirculating aquaculture systems and probiotics have contributed to enhancing aquaculture sustainability and reducing the need for high loads of antibiotics and other chemicals. Furthermore, biotechnological tools (e.g., omics and cell biology) have shed light on cellular processes in the health and disease of reared organisms. Metagenomics is a reliable and relatively quick tool to identify microbial communities in aquaculture settings.