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To better understand bacterial communities and metabolism under nitrogen deficiency, 154 seawater samples were obtained from 5 to 200 m at 22 stations in the photic zone of the Western North Pacific Ocean. Total 634 nitrate-utilizing bacteria were isolated using selective media and culture-dependent methods, and 295 of them were positive for nitrate reduction. These nitrate-reducing bacteria belonged to 19 genera and 29 species and among them, Qipengyuania flava, Roseibium aggregatum, Erythrobacter aureus, Vibrio campbellii, and Stappia indica were identified from all tested seawater layers of the photic zone and at almost all stations. Twenty-nine nitrate-reducing strains representing different species were selected for further the study of nitrogen, sulfur, and carbon metabolism. All 29 nitrate-reducing isolates contained genes encoding dissimilatory nitrate reduction or assimilatory nitrate reduction. Six nitrate-reducing isolates can oxidize thiosulfate based on genomic analysis and activity testing, indicating that nitrate-reducing thiosulfate-oxidizing bacteria exist in the photic zone. Five nitrate-reducing isolates obtained near the chlorophyll a-maximum layer contained a dimethylsulfoniopropionate synthesis gene and three of them contained both dimethylsulfoniopropionate synthesis and cleavage genes. This suggests that nitrate-reducing isolates may participate in dimethylsulfoniopropionate synthesis and catabolism in photic seawater. The presence of multiple genes for chitin degradation and extracellular peptidases may indicate that almost all nitrate-reducing isolates (28/29) can use chitin and proteinaceous compounds as important sources of carbon and nitrogen. Collectively, these results reveal culturable nitrate-reducing bacterial diversity and have implications for understanding the role of such strains in the ecology and biogeochemical cycles of nitrogen, sulfur, and carbon in the oligotrophic marine photic zone. [ABSTRACT FROM AUTHOR]

The Gram-stain-negative, golden-yellow-colored, non-spore-forming, strictly aerobic, slender rod-shaped bacterial strain, designated KN852T, was isolated from a seamount in the tropical western Pacific. The predominant respiratory quinone was MK-7 and the polar lipid profiles contained phosphatidylethanolamine, one unidentified phospholipid and six unidentified polar lipids. The predominant cellular fatty acids were iso-C15:0, summed feature 3(C16:1ω7c and/or iso-C15:0 2OH), iso-C17:0 3OH and iso-C15:1 G. Phylogenetic analyses of 16S rRNA gene sequence revealed that strain KN852T was affiliated with the family Flammeovirgaceae of the phylum Bacteroidota and formed a distinct lineage. The genomic DNA G + C content of strain KN852T was 34.8%. Collectively, based on phenotypic, chemotaxonomic, phylogenetic and genomic evidence presented, strain KN852T represents a novel species of a novel genus of the family Flammeovirgaceae, for which the name Marinigracilibium pacificum gen. nov., sp. nov. is proposed. The type strain is KN852T (= CGMCC 1.17119T = KCTC 72433T). [ABSTRACT FROM AUTHOR]

The Gram-stain-negative, strictly aerobic, curved-to-spiral rod-shaped bacterial strain, designated KN72T, was isolated from the Caroline Seamounts in the Pacific Ocean. Phylogenetic analysis of 16S rRNA gene sequences revealed that strain KN72T was a member of the family Rhodospirillaceae and formed a distinct lineage. Strain KN72T contained ubiquinone-10 as the major respiratory quinone. The polar lipid profiles contained phosphatidylethanolamine, phosphatidylglycerol, one aminolipid and three phospholipids. The predominant cellular fatty acids were C16:0 and summed feature 8 (comprising C18:1ω7c/C18:1ω6c). The strain KN72T displayed highest 16S rRNA gene sequence similarities with Hwanghaeella grinnelliae Gri0909T (92.3%), Marivibrio halodurans ZB80T (91.0%) and Aestuariispira insulae AH-MY2T (90.1%). The DNA G+C content of strain KN72T was 61.1%. Collectively, based on phenotypic, chemotaxonomic, phylogenetic and genomic evidence presented, strain KN72T represents a novel species of a novel genus of the family Rhodospirillaceae, for which the name Pacificispira spongiicola gen. nov., sp. nov. is proposed. The type strain is KN72T (= CGMCC 1.17142T = KCTC 72429T). [ABSTRACT FROM AUTHOR]

Two Gram-stain-positive, facultatively anaerobic, rod-shaped bacterial strains, S126T and S82T, were isolated from coastal algae of China. Strains S126T and S82T are halotolerant and could grow in the presence of 0–13% NaCl and 0–14% NaCl, respectively. The two strains shared 98.9% 16S rRNA gene sequence similarity with each other and 93.4–99.8% similarity with type strains of Exiguobacterium species. The major fatty acids (> 10%) of strains S126T and S82T were iso-C17:0, iso-C13:0, anteiso-C13:0 and iso-C15:0. The predominant quinones of strains S126T and S82T were MK-7 and MK-8. The polar lipid profiles of strain S126T and S82T contained diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The cell-wall peptidoglycans of both strains S126T and S82T were of the A3α L-Lys-Gly type. The average nucleotide identity (ANI) and average nucleotide index (AAI) between strains S126T and S82T and type strains of Exiguobacterium species were all below the thresholds to discriminate bacterial species, indicating that they constitute two novel species in the genus Exiguobacterium. Based on polyphasic taxonomy characterization and genomic aspects, the names Exiguobacterium algae sp. nov. and Exiguobacterium qingdaonense sp. nov. are proposed for the two novel species, with type strains being S126T (= CGMCC 1.17116T = KCTC 43079 T) and S82T (= CGMCC 1.17115T = KCTC 43078T), respectively. [ABSTRACT FROM AUTHOR]

Lignin bio-valorization is an emerging field of applied biotechnology and has not yet been studied at low temperatures. Paraburkholderia aromaticivorans AR20-38 was examined for its potential to degrade six selected lignin monomers (syringic acid, p-coumaric acid, 4-hydroxybenzoic acid, ferulic acid, vanillic acid, benzoic acid) from different upper funneling aromatic pathways. The strain degraded four of these compounds at 10°C, 20°C, and 30°C; syringic acid and vanillic acid were not utilized as sole carbon source. The degradation of 5 mM and 10 mM ferulic acid was accompanied by the stable accumulation of high amounts of the value-added product vanillic acid (85–89% molar yield; 760 and 1540 mg l−1, respectively) over the whole temperature range tested. The presence of essential genes required for reactions in the upper funneling pathways was confirmed in the genome. This is the first report on biodegradation of lignin monomers and the stable vanillic acid production at low and moderate temperatures by P. aromaticivorans. Key points: • Paraburkholderia aromaticivorans AR20-38 successfully degrades four lignin monomers. • Successful degradation study at low (10°C) and moderate temperatures (20–30°C). • Biotechnological value: high yield of vanillic acid produced from ferulic acid. [ABSTRACT FROM AUTHOR]

The Gram-stain-negative, aerobic, ovoid or rod-shaped bacterial strain, designated KN286T, was isolated from seawater of tropical western Pacific. Growth occurred between 15 and 40 °C (optimally at 30–35 °C), pH 6–9 (optimally at 7.0) and in the presence of 0.5–5.0% (w/v) NaCl (optimally between 2.0 and 3.0%). Strain KN286T contained Q-10 as the major respiratory quinone. The polar lipid profile contained phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, three phospholipids, three glycolipids, and three unidentified polar lipids. The predominant cellular fatty acid was summed feature 8 (composed of C18:1ω7c and/or C18:1ω6c). Phylogenetic analysis of the 16S rRNA gene sequence revealed that strain KN286T was a member of the family Rhodobacteraceae and formed a distinct lineage. Strain KN286T has a genome size of 3.25 Mbp and a G + C content of 65.0 mol%. It encoded with some genes for carbohydrate-active enzymes, such as GH20 (Glycoside Hydrolase Family 20) and PL1 (Polysaccharide Lyase Family 1) and did not encode with a set of genes for reduction of nitrate to nitrite (nitrate reductase gamma subunit, respiratory nitrate reductase alpha N-terminal and respiratory nitrate reductase beta C-terminal). Based on phylogenetic analyses with single-copy orthologous clusters, low isDDH value (19.6%), low ANI (72.4%) and low AAI (65.7%) results, differential chemotaxonomic and physiological properties, strain KN286T represents a novel species of a novel genus of the family Rhodobacteraceae, for which the name Oceanomicrobium pacificus gen. nov., sp. nov. is proposed. The type strain of Oceanomicrobium pacificus is KN286T (=CGMCC 1.17118T = KCTC 72430T). [ABSTRACT FROM AUTHOR]

Magnetic resonance (MR) technology has been widely employed in scientific research, clinical diagnosis and geological survey. However, the fabrication of MR radio frequency probeheads still face difficulties in integration, customization and miniaturization. Here, we utilized 3D printing and liquid metal filling techniques to fabricate integrative radio frequency probeheads for MR experiments. The 3D-printed probehead with micrometer precision generally consists of liquid metal coils, customized sample chambers and radio frequency circuit interfaces. We screened different 3D printing materials and optimized the liquid metals by incorporating metal microparticles. The 3D-printed probeheads are capable of performing both routine and nonconventional MR experiments, including in situ electrochemical analysis, in situ reaction monitoring with continues-flow paramagnetic particles and ions separation, and small-sample MR imaging. Due to the flexibility and accuracy of 3D printing techniques, we can accurately obtain complicated coil geometries at the micrometer scale, shortening the fabrication timescale and extending the application scenarios. Here, the authors combine 3D printing and liquid metal filling techniques to fabricate customised probeheads for magnetic resonance experiments. They demonstrate in situ electrochemical nuclear magnetic resonance analysis, reaction monitoring with continues-flow separation and small-sample imaging. [ABSTRACT FROM AUTHOR]

This paper proposed a novel variable optical splitter, of which the splitting ratio can be dynamically adjusted according to different wavelengths. A novel intelligent passive optical network (PON) system based on this splitter was also presented. Experimental results demonstrated that the insertion loss can be reduced corresponding to the decrease of the splitting ratio. [ABSTRACT FROM AUTHOR]

We characterized the culturable, heterotrophic bacterial community in soil collected from a former alpine military site contaminated with petroleum hydrocarbons. The physiologically active eubacterial community, as revealed by fluorescence-in situ-hybridization, accounted for 14.9 % of the total (DAPI-stained) bacterial community. 4.0 and 1.2 % of the DAPI-stained cells could be attributed to culturable, heterotrophic bacteria able to grow at 20 and 10 °C, respectively. The majority of culturable bacterial isolates (23/28 strains) belonged to the Proteobacteria with a predominance of Alphaproteobacteria. The remaining isolates were affiliated with the Firmicutes, Actinobacteria and Bacteroidetes. Five strains could be identified as representatives of novel species. Characterization of the 28 strains demonstrated their adaptation to the temperature and nutrient conditions prevailing in the studied soil. One-third of the strains was able to grow at subzero temperatures (−5 °C). Studies on the effect of temperature on growth and lipase production with two selected strains demonstrated their low-temperature adaptation. [ABSTRACT FROM AUTHOR]

Totally more than 500 yeast strains were isolated from seawater, sea sediments, mud of sea salterns, marine fish guts and marine algae. The results of routine and molecular biology identification methods show that nine strains among these marine yeasts belong to Aureobasidium pullulans, although the morphologies of their colonies are very different. The marine yeasts isolated from different marine environments indicate that A. pullulans is widely distributed in different environmental conditions. These Aureobasidium pullulans strains include A. pullulans 4#2, A. pullulans N13d, A. pullulans HN3-11, A. pullulans HN2-3, A. pullulans JHSc, A. pullulans HN4.7, A. pullulans HN5.3, A. pullulans HN6.2 and A. pullulans W13a. A. pullulans 4#2 could produce cellulase and single cell protein. A. pullulans N13d could produce protease, lipase, amylase and cellulase. Both A. pullulans HN3-11 and A. pullulans HN2-3 were able to produce protease, lipase and cellulase. A. pullulans JHSc could secrete cellulase and killer toxin. Both A. pullulans HN4.7 and A. pullulans HN5.3 could yield lipase and cellulase. A. pullulans W13a was able to secrete extracellular amylase and cellulase while A. pullulans HN4.7 and A. pullulans N13d could produce siderophores. This means that different A. pullulans strains from different marine environments have different physiological characteristics, which may be applied in many different biotechnological industries. [ABSTRACT FROM AUTHOR]

A total of 317 yeast isolates from seawater, sediments, mud of salterns, guts of marine fishes and marine algae were obtained. The results of routine identification and molecular characterization showed that six isolates among these marine yeasts belonged to Candida genus as Candida intermedia for YA01a, Candida parapsilosis for 3eA2, Candida quercitrusa for JHSb, Candia rugosa for wl8, Candida zeylanoides for TJY13a, and Candida membranifaciens for W14-3. Isolates YA01a ( Candida intermedia), wl8 ( Candida rugosa), 3eA2 ( Candida parapsilosis), and JHSb ( Candida quercitrusa) were found producing cell-bound lipase, while isolate W14-3 ( Candida membranifaciens) producing riboflavin. These marine yeast Candida spp. seem to have wide potential applications in biotechnology. [ABSTRACT FROM AUTHOR]

The concept of double primary lung cancer (DPLC) has been generally accepted. Recently, an increasing incidence of synchronous DPLC has been reported, while the diagnostic standard and treatment strategies remain to be improved. This study was conducted to investigate effective surgical treatment and prognosis of synchronous DPLC. From January 1983 to April 2004, 31 patients with synchronous DPLC were operated in our department. Clinical data, such as surgical pattern, postoperative complications, and survival status, of all these patients were reviewed retrospectively. The 31 patients with synchronous DPLC accounted for 0.67% of all the 4,649 patients operated for primary lung cancer in our department during the same period. Both tumors of the synchronous DPLC were resected with lobectomy or pneumonectomy in 12 patients, while among the other 19 patients at least 1 tumor was treated with partial pulmonary resection. The postoperative morbidity was 29% (9/31), including 1 case of respiratory insufficiency, 3 cases of atelectasis, 2 cases of atrial fibrillation, 1 case of haemoptysis, 1 case of pleural effusion, and 1 case of wound fat necrosis. No deaths occurred during the operations or within 30 days postoperatively. The postoperative 1 -, 3-, and 5-year survival rates were 52%, 29%, and 20%, respectively. The incidence of synchronous DPLC is low. An aggressive and reasonable surgical approach can achieve a satisfactory outcome in patients with synchronous DPLC. The postoperative morbidity is low. Some patients might achieve long-term survival. [ABSTRACT FROM AUTHOR]

Ultra-low-loss and large-effective-area fiber has been successfully applied in transoceanic transmission, which is considered as a promising candidate for 100 Gbit/s and beyond 100 Gbit/s coherent long-haul terrestrial optical networks. Several theoretical and experimental investigations have been reported, including provincial terrestrial field trial. To support long-haul terrestrial application, it is urgent to prove that the ultra-low-loss and large-effective-area fiber after terrestrial deployment can significantly enhance the performance of long-haul transmission over 1000 km compared with the conventional single mode fiber. In this paper, we extended our previous work and summarized design methods for complex terrestrial environment. To verify the fiber characteristics in long-haul terrestrial transmission, we installed the longest terrestrial ultra-low-loss and large-effective-area fiber link in the world with a total length of 1539.6 km. The results show that the transmission performances of wavelength-division-multiplexed signals with per-channel data rates of 100 Gbit/s, 200 Gbit/s, and 400 Gbit/s over the ultra-low-loss and large-effective-area fiber are all obviously improved, demonstrating that this fiber is more suitable for ultrahigh-speed long-haul terrestrial transmission. [ABSTRACT FROM AUTHOR]