Screening and characterization of proteases produced by deep-sea cold seep bacteria

Author(s):  
Chenchen Guo ◽  
Chaomin Sun ◽  
Shimei Wu
Keyword(s):  
Deep Sea ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 802
Author(s):  
Chenchen Guo ◽  
Rikuan Zheng ◽  
Ruining Cai ◽  
Chaomin Sun ◽  
Shimei Wu

The deep ocean microbiota has unexplored potential to provide enzymes with unique characteristics. In order to obtain cold-active lipases, bacterial strains isolated from the sediment of the deep-sea cold seep were screened, and a novel strain gcc21 exhibited a high lipase catalytic activity, even at the low temperature of 4 °C. The strain gcc21 was identified and proposed to represent a new species of Pseudomonas according to its physiological, biochemical, and genomic characteristics; it was named Pseudomonas marinensis. Two novel encoding genes for cold-active lipases (Lipase 1 and Lipase 2) were identified in the genome of strain gcc21. Genes encoding Lipase 1 and Lipase 2 were respectively cloned and overexpressed in E. coli cells, and corresponding lipases were further purified and characterized. Both Lipase 1 and Lipase 2 showed an optimal catalytic temperature at 4 °C, which is much lower than those of most reported cold-active lipases, but the activity and stability of Lipase 2 were much higher than those of Lipase 1 under different tested pHs and temperatures. In addition, Lipase 2 was more stable than Lipase 1 when treated with different metal ions, detergents, potential inhibitors, and organic solvents. In a combination of mutation and activity assays, catalytic triads of Ser, Asp, and His in Lipase 1 and Lipase 2 were demonstrated to be essential for maintaining enzyme activity. Phylogenetic analysis showed that both Lipase 1 and Lipase 2 belonged to lipase family III. Overall, our results indicate that deep-sea cold seep is a rich source for novel bacterial species that produce potentially unique cold-active enzymes.


Author(s):  
Yuan-yuan Sun ◽  
Hai-zhen Zhou ◽  
Qing-lei Sun
Keyword(s):  
Deep Sea ◽  

Marine Drugs ◽  
2020 ◽  
Vol 19 (1) ◽  
pp. 9
Author(s):  
Ya-Ping Liu ◽  
Sheng-Tao Fang ◽  
Zhen-Zhen Shi ◽  
Bin-Gui Wang ◽  
Xiao-Nian Li ◽  
...  

Three new phenylhydrazones, penoxahydrazones A–C (compounds 1–3), and two new quinazolines, penoxazolones A (compound 4) and B (compound 5), with unique linkages were isolated from the fungus Penicillium oxalicum obtained from the deep sea cold seep. Their structures and relative configurations were assigned by analysis of 1D/2D NMR and mass spectroscopic data, and the absolute configurations of 1, 4, and 5 were established on the basis of X-ray crystallography or ECD calculations. Compound 1 represents the first natural phenylhydrazone-bearing steroid, while compounds 2 and 3 are rarely occurring phenylhydrazone tautomers. Compounds 4 and 5 are enantiomers that feature quinazoline and cinnamic acid units. Some isolates exhibited inhibition of several marine phytoplankton species and marine-derived bacteria.


BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Oluchi Aroh ◽  
Kenneth M. Halanych

Abstract Background Long Terminal Repeat retrotransposons (LTR retrotransposons) are mobile genetic elements composed of a few genes between terminal repeats and, in some cases, can comprise over half of a genome’s content. Available data on LTR retrotransposons have facilitated comparative studies and provided insight on genome evolution. However, data are biased to model systems and marine organisms, including annelids, have been underrepresented in transposable elements studies. Here, we focus on genome of Lamellibrachia luymesi, a vestimentiferan tubeworm from deep-sea hydrocarbon seeps, to gain knowledge of LTR retrotransposons in a deep-sea annelid. Results We characterized LTR retrotransposons present in the genome of L. luymesi using bioinformatic approaches and found that intact LTR retrotransposons makes up about 0.1% of L. luymesi genome. Previous characterization of the genome has shown that this tubeworm hosts several known LTR-retrotransposons. Here we describe and classify LTR retrotransposons in L. luymesi as within the Gypsy, Copia and Bel-pao superfamilies. Although, many elements fell within already recognized families (e.g., Mag, CSRN1), others formed clades distinct from previously recognized families within these superfamilies. However, approximately 19% (41) of recovered elements could not be classified. Gypsy elements were the most abundant while only 2 Copia and 2 Bel-pao elements were present. In addition, analysis of insertion times indicated that several LTR-retrotransposons were recently transposed into the genome of L. luymesi, these elements had identical LTR’s raising possibility of recent or ongoing retrotransposon activity. Conclusions Our analysis contributes to knowledge on diversity of LTR-retrotransposons in marine settings and also serves as an important step to assist our understanding of the potential role of retroelements in marine organisms. We find that many LTR retrotransposons, which have been inserted in the last few million years, are similar to those found in terrestrial model species. However, several new groups of LTR retrotransposons were discovered suggesting that the representation of LTR retrotransposons may be different in marine settings. Further study would improve understanding of the diversity of retrotransposons across animal groups and environments.


Sensors ◽  
2021 ◽  
Vol 21 (15) ◽  
pp. 5090
Author(s):  
Qingsheng Liu ◽  
Jinjia Guo ◽  
Wangquan Ye ◽  
Kai Cheng ◽  
Fujun Qi ◽  
...  

As a powerful in situ detection technique, Raman spectroscopy is becoming a popular underwater investigation method, especially in deep-sea research. In this paper, an easy-to-operate underwater Raman system with a compact design and competitive sensitivity is introduced. All the components, including the optical module and the electronic module, were packaged in an L362 × Φ172 mm titanium capsule with a weight of 20 kg in the air (about 12 kg in water). By optimising the laser coupling mode and focusing lens parameters, a competitive sensitivity was achieved with the detection limit of SO42− being 0.7 mmol/L. The first sea trial was carried out with the aid of a 3000 m grade remotely operated vehicle (ROV) “FCV3000” in October 2018. Over 20,000 spectra were captured from the targets interested, including methane hydrate, clamshell in the area of cold seep, and bacterial mats around a hydrothermal vent, with a maximum depth of 1038 m. A Raman peak at 2592 cm−1 was found in the methane hydrate spectra, which revealed the presence of hydrogen sulfide in the seeping gas. In addition, we also found sulfur in the bacterial mats, confirming the involvement of micro-organisms in the sulfur cycle in the hydrothermal field. It is expected that the system can be developed as a universal deep-sea survey and detection equipment in the near future.


2013 ◽  
Vol 132 ◽  
pp. 178-181 ◽  
Author(s):  
Yin Chen ◽  
Wenjun Mao ◽  
Baofeng Wang ◽  
Lina Zhou ◽  
Qianqun Gu ◽  
...  

Author(s):  
Sabine Stöhr ◽  
Michel Segonzac

The animal communities associated with the deep-sea reducing environment have been studied for almost 30 years, but until now only a single species of ophiuroid, Ophioctenella acies, has been found at both hydrothermal vents and methane cold seeps. Since the faunal overlap between vent and seep communities is small and many endemic species have been found among other taxa (e.g. Mollusca, Crustacea), additional species of ophiuroids were expected at previously unstudied sites. Chemical compositions at reducing sites differ greatly from the nearby bathyal environment. Generally, species adapted to chemosynthetic environments are not found in non-chemosynthetic habitats, but occasional visitors of other bathyal species to vent and seep sites have been recorded among many taxa except ophiuroids. This paper presents an analysis of the ophiuroid fauna found at hydrothermal vents and non-reducing nearby sites on the Mid-Atlantic Ridge and on methane cold seeps in the Gulf of Mexico, at Blake Ridge off South Carolina and south of Barbados. In addition to O. acies, four species were found at vents, Ophiactis tyleri sp. nov., Ophiocten centobi, Ophiomitra spinea and Ophiotreta valenciennesi rufescens. While Ophioctenella acies appears to be restricted to chemosynthetic areas, the other four species were also found in other bathyal habitats. They also occur in low numbers (mostly single individuals), whereas species adapted to hydrothermal areas typically occur in large numbers. Ophioscolex tripapillatus sp. nov. and Ophiophyllum atlanticum sp. nov. are described from nearby non-chemosynthetic sites. In a cold seep south of Barbados, three species of ophiuroids were found, including Ophioctenella acies, Amphiura sp., Ophiacantha longispina sp. nov. and Ophioplinthaca chelys. From the cold seeps at Blake Ridge and the Gulf of Mexico, Ophienigma spinilimbatum gen. et sp. nov. is described, likely restricted to the reducing environment. Ophiotreta valenciennesi rufescens occurred abundantly among Lophelia corals in the Gulf of Mexico seeps, which is the first record of this species from the West Atlantic. Habitat descriptions complement the taxonomic considerations, and the distribution of the animals in reducing environments is discussed.


PLoS ONE ◽  
2017 ◽  
Vol 12 (3) ◽  
pp. e0173750 ◽  
Author(s):  
Ramón Alberto Batista-García ◽  
Thomas Sutton ◽  
Stephen A. Jackson ◽  
Omar Eduardo Tovar-Herrera ◽  
Edgar Balcázar-López ◽  
...  
Keyword(s):  

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