Lycodes nishimurai, a new deep-sea eelpout (Teleostei: Zoarcidae) from the Sea of Japan

A new zoarcid fish, Lycodes nishimuari, is described on the basis of four specimens from the Yamato Bank, the Sea of Japan, at depths of 642–669 m. Although this species resembles Lycodes diapterus, L. hubbsi, L. pectoralis, L. macrochir, and L. nakamurae in having a deep notch in the pectoral fin and a single lateral line on the body, it is distinguished from them by the following combination of characters: no scales on pectoral fin base; scales on dorsum before dorsal fin origin; suborbital, preopercular, and last postorbital pores with risen rim; whitish lips; no whitish transverse bars on body; pectoral fin membrane and anterior part of dorsal fin membrane without black spots; basal color of vertical fins black. Supplementary material to this paper is available in electronic format at .     

Lithocarols A-F,six tenellone derivatives from the deep-sea derived fungus Phomopsis lithocarpus FS508

Lithocarols A-F (1–6) possessing novel highly-oxygenated isobenzofuran core, together with a related known compound isoprenylisobenzofuran A (7) were isolated from the marine-derived fungus Phomopsis lithocarpus FS508. Among them, lithocarols A-E (1–5) represent the first examples of poly-ketal derivatives in tenellone family. The structures for all these compounds were fully elucidated by spectroscopic analysis, X-ray diffraction, and electronic circular dichroism calculations. Their cytotoxic assay disclosed that compounds 1–4 displayed moderate growth inhibitory effect against four human tumor cell lines with the IC₅₀ values ranging from 10.5 to 38.7 μM.     

Nematode and macrofaunal diversity in central Arctic Ocean benthos

Deep-sea diversity studies have revealed intriguing patterns on both local and regional scales, but there is insufficient evidence with which to evaluate these trends in the Arctic Ocean basin. We collected data on the diversity of benthic macrofauna and meiofaunal nematodes along two transects from the shelf margin to the North Pole. Contrary to prevailing paradigms, there was no change in diversity with depth between 1000 and 4273 m. There was a trend, however, toward reduced taxonomic richness for both macrofauna and nematodes with increasing latitude. Regional (β-) diversity differences were not observed for nematodes, but significant contrasts in Bray-Curtis similarity-based community structure of macrofauna were seen between the Eurasian and Amerasian Basins, as well as between the Lomonosov and Mendeleev Ridges. Since fauna within the deep Arctic Ocean appear to represent a single species pool, we suggest that both local (α-) and β-diversity may be determined by ecological processes in the Arctic, and are not the consequence of historical or evolutionary processes. Furthermore, insights gained from studies of benthic-pelagic coupling, known to play a significant role in determining benthic community structure and function at high latitudes, may also be useful in investigations of Arctic biodiversity. This model may be valuable in designing future studies of biodiversity, and for predicting potential impacts of climate change on diversity patterns.     

Spatial and bathymetric trends in Harpacticoida (Copepoda) community structure in the Northern Gulf of Mexico deep-sea

Harpacticoid copepod community structure was analyzed at 43 stations in the northern Gulf of Mexico deep-sea to test regional and bathymetric patterns of diversity in relation to environmental variables and topographic complexity of the continental slope. Depth, longitude, and proximity to the Florida Escarpment significantly affect average phylogenetic diversity, but basins and canyons do not. Multivariate analysis reveals a significant inverse relationship between diversity and POM flux, which is confirmed by significant region-scale depth and longitude differences. Although species richness declines linearly with increasing depth, the expected number of species (rarefraction) is maximized at approximately 1200 m, and average taxonomic and phylogenetic diversity continue to increase with depth, suggesting greater morphological or functional harpacticoid diversity with increasing depth. Most stations have unique species compositions, suggesting high regional (2200 species) and global (10⁵-10⁶ species) diversity by extrapolation. Therefore, processes maintaining harpacticoid diversity in the northern Gulf of Mexico deep-sea seem to rely on both small-scale dispersal and large-scale food supply mechanisms.     

菲律宾海北部底质沉积中的深海介形类

对琉球群岛东侧的菲律宾海北部海区(27.0°-30.0°N,129.5°-135.5°E)水深1 666 m至6 616 m的123个表层沉积物样品进行了定量微体古生物学研究.仅在38个样品中发现介形类,主要分布在4 000 m以浅水深区.初步鉴定有21属35种,其中Krithe在样品中的出现率和丰度最高,其次常见的还...     

南海深海微生物酯酶EST12-7在制备(R)-2-氯丙酸乙酯中的应用研究

利用来源南海深海的微生物酯酶EST12-7不对称水解反应拆分制备（R）-2-氯丙酸乙酯。并探寻了温度、pH、底物浓度、有机溶剂和反应时间等因素对酯酶EST12-7催化制备（R）-2-氯丙酸乙酯的影响。结果表明,深海微生物酯酶EST12-7催化制备（R）-2-氯丙酸乙酯的最佳反应条件为：13.8 μg/ml酯酶EST12-7,50 mmol/L（±）-2-氯丙酸乙酯,2%正癸醇,pH8.5,30℃,0.05mol/L Tris-HCl,反应60 min。在最佳反应条件下,（±）-2-氯丙酸乙酯的转化率可达49%,所制备的（R）-2-氯丙酸乙酯的光学纯度为98%。通过对酯酶EST12-7拆分制备（R）-2-氯丙酸甲酯和（R）-2-氯丙酸乙酯进行比较,2-氯丙酸酯中的链长对酯酶EST12-7拆分反应有极大的影响。     

Nature and role of newly described symbiotic associations between a sea anemone and gastropods at bathyal depths in the NW Atlantic

The hormathiid sea anemone Allantactis parasitica was found living as an epibiont on numerous species of gastropods at depths of 725-1100 m along the continental slope of eastern Canada. The proportion of bathyal gastropods hosting 1-6 sea anemones reached 72.5% in a single trawl. Although A. parasitica was occasionally found on other substrata (i.e. empty shells, pebbles), laboratory trials confirmed that they preferably associate with living gastropods. Settlement of planula larvae occurred significantly more often on the shells of live bathyal gastropods than on all other substrata present in the tanks. Juvenile sea anemones (∼ 1 mm diameter) readily moved from the mud or other inert substrata onto shells of burrowed bathyal gastropods. Conversely, larvae, juveniles and adults of A. parasitica never associated with any shallow-water gastropods when given the opportunity. Trials exposing predatory sea stars (Leptasterias polaris) from shallow and bathyal depths to bathyal gastropods (Buccinum undatum) with epibiotic A. parasitica, and to asymbiotic bathyal and shallow-water B. undatum, revealed adaptive behaviours in both prey and predator. Shallow-water gastropods (devoid of epibionts) reacted defensively to L. polaris, whereas bathyal gastropods relied mostly on their epibionts to protect them, thus falling prey to L. polaris when the epibionts were removed. L. polaris from bathyal depths typically ignored symbiotic gastropods, but they consistently preyed on asymbiotic ones, while L. polaris from shallow areas initially attempted to prey on all gastropods, but learned to avoid those harbouring sea anemones. Furthermore, living as epibionts afforded sea anemones a means to escape one of their own predators, the sea star Crossaster papposus. The mutualistic relationship between hormathiid sea anemones and bathyal gastropods from the NW Atlantic may have evolved in response to predation pressure.     

热带太平洋深海微生物抗肿瘤活性的初步研究

以４个人体癌细胞株为模型、利用四甲基偶氮唑盐（Methyl Thiazolyl blue Tetrazolium bromide,MTT）比色法和磺酰罗丹明（SulfoRhodamine B,SRB）染色法对55株来自于热带太平洋深海微生物（细菌和霉菌）的培养液的乙酸乙酯抽提物以及菌体的甲醇提取物进行了细胞毒活性筛选,并主要采用分子生物学方法鉴定了该批菌株. 结果表明,55株微生物发酵样品共１１０个提取物中,９０％样品表现出细胞毒活性;其中13株微生物的活性较强（提取物有效抑制浓度≤16μg/ml）,具有较好的开发应用前景。同时还发现,菌体中检测到的活性菌株数大于发酵液中检测到的活性菌株数, 细菌的筛选得率高于霉菌的筛选得率.鉴定结果显示, 50株微生物分属于21属、29种,其中１３个较高活性菌株来源于８个属。本文为我国深海微生物资源的开发利用,提供了探索性研究信息。     

Extracellular hydrolytic enzyme screening of culturable heterotrophic bacteria from deep-sea sediments of the Southern Okinawa Trough

The Southern Okinawa Trough is an area of focused sedimentation due to particulate matter export from the shelf of the East China Sea and the island of Taiwan. In order to understand the geomicrobiological characteristics of this unique sedimentary environment, bacterial cultivations were carried out for an 8.61 m CASQ core sediment sample. A total of 98 heterotrophic bacterial isolates were characterized based on 16S rRNA gene phylogenetic analysis. These isolates can be grouped into four bacterial divisions, including 13 genera and more than 20 species. Bacteria of the γ-Proteobacteria lineage, especially those from the Halomonas (27 isolates) and Psychrobacter (20 isolates) groups, dominate in the culturable bacteria assemblage. They also have the broadest distribution along the depth of the sediment. More than 72.4% of the isolates showed extracellular hydrolytic enzyme activities, such as amylases, proteases, lipases and Dnases, and nearly 59.2% were cold-adapted exoenzyme-producers. Several Halomonas strains show almost all the tested hydrolases activities. The wide distribution of exoenzyme activities in the isolates may indicate their important ecological role of element biogeochemical cycling in the studied deep-sea sedimentary environment.