Jih-Terng Wang

Endozoicomonas montiporae sp. nov., isolated from the encrusting pore coral Montipora aequituberculata

A Gram-negative, aerobic, rod-shaped bacterium, designated strain CL-33(T), was isolated from the encrusting pore coral Montipora aequituberculata collected from seawater off the coast of southern Taiwan. 16S rRNA gene sequence analysis showed that the strain clustered closely with Endozoicomonas elysicola MKT110(T) (96.7 % similarity). The novel strain required NaCl for growth and exhibited optimal growth at 25 degrees C and in the presence of 2-3 % NaCl. Predominant cellular fatty acids were summed feature 3 (C(16 : 1)omega7c and/or C(16 : 1)omega6c; 39.6 %), summed feature 8 (C(18 : 1)omega7c and/or C(18 : 1)omega6c; 32.8 %) and C(16 : 0) (12.0 %). The DNA G+C content of strain CL-33(T) was 50.0 mol%. The results of physiological and biochemical tests allowed the clear phenotypic differentiation of this isolate from E. elysicola. It is evident from the genotypic, phenotypic and chemotaxonomic data presented that strain CL-33(T) represents a novel species of the genus Endozoicomonas, for which the name Endozoicomonas montiporae sp. nov. is proposed. The type strain is CL-33(T) (=LMG 24815(T) =BCRC 17933(T)).

Chitinimonas taiwanensis gen. nov., sp. nov., a novel chitinolytic bacterium isolated from a freshwater pond for shrimp culture.

A bacterial strain, designated cfT was isolated from surface water of a freshwater pond for shrimp (Macrobrachium rosenbergii) culture at Ping-Tung (Southern Taiwan). Cells of this organism were Gram-negative, slightly curved rods which were motile by means of a single polar flagellum. Strain cfT utilized chitin as the exclusive carbon, nitrogen, and energy source for growth, both under aerobic and anaerobic conditions. Optimum conditions for growth were between 25 and 37 degrees C, 0 and 1% NaCl and pH 6 to 8. Strain cfT secreted two chitinolytic enzymes with approximate molecular weight 52 and 64 kDa, which hydrolyzed chitin to produce chitotriose as major product. Sequence comparison of an almost complete 16S rDNA gene showed less than 92% sequence similarity with known bacterial species. Phylogenetic analysis based on the neighbour-joining and other methods indicated that the organism formed a distinct lineage within the beta-subclass of Proteobacteria. The predominant cellular fatty acids of strain cfT were hexadecanoic acid (about 29%), octadecenoic acid (about 12%) and summed feature 3 (16:1 omega7c or 15 iso 2-OH or both [about 49%]). Its DNA base ratio was 62.8 mol% G+C. We propose to classify strain cfT (= CCRC 17210T = LMG 22011T) as Chitinimonas taiwanensis gen. nov., sp. nov.

Tenacibaculum aiptasiae sp. nov., isolated from a sea anemone Aiptasia pulchella.

A novel bacterial strain, designated a4T, isolated from a sea anemone (Aiptasia pulchella) in Taiwan, was characterized using a polyphasic taxonomic approach. Strain a4T was aerobic, Gram-negative, pale-yellow-pigmented and rod-shaped. It grew optimally at 30-35 degrees C, in the presence of 3-4 % (w/v) NaCl and at pH 8.0. Phylogenetic analyses based on 16S rRNA gene sequences showed that the strain belonged to the genus Tenacibaculum (family Flavobacteriaceae, phylum Bacteroidetes). The closest neighbours were Tenacibaculum lutimaris TF-26T (97.6 % similarity) and Tenacibaculum aestuarii SMK-4T (97.7 % similarity). The novel isolate could be distinguished from all Tenacibaculum species by several phenotypic characteristics. The major fatty acids were summed feature 3 (comprising C16 : 1 omega 7c and/or iso-C15 : 0 2-OH, 19.6 %), iso-C15 : 0 (12.9 %), iso-C16 : 0 3-OH (10.2 %), iso-C17 : 0 3-OH (9.9 %) and iso-C15 : 1 (9.5 %). The DNA G+C content was 35.0 mol%. Hence, genotypic and phenotypic data demonstrate that strain a4(T) should be classified as a representative of a novel species in the genus Tenacibaculum, for which the name Tenacibaculum aiptasiae sp. nov. is proposed. The type strain is a4T (=BCRC 17655T =LMG 24004T).

Symbiont communities and host genetic structure of the brain coral Platygyra verweyi, at the outlet of a nuclear power plant and adjacent areas

In the context of rising seawater temperatures associated with climate change,  the issue of whether coral holobionts deal with this challenge by shuffling their associations with stress‐ and/or heat‐tolerant Symbiodinium, by generating heat‐resistant host genotypes, or both is important for coral survival. In this study, the composition of communities of the endosymbiont Symbiodinium and the population genetics of the coral host Platygyra verweyi were examined in a reef impacted by hot‐water discharged from the outlet of a nuclear power plant in operation in Kenting, Southern Taiwan since 1984. The water at this site is 2.0–3.0 °C warmer than adjacent reefs in summer, which have an average seawater temperature of 29.0 °C. The data were compared with those for the same species at other sites within 12 km of the outlet site. Platygyra verwyei was associated with one or both of Symbiodinium types C3 (heat sensitive) and D1a (heat tolerant) at all sites with the latter being the dominant at the nuclear power plant outlet. The proportion of C3 in populations increased gradually with increasing distance from the hot‐water discharge. Genetic analysis of the Platygyra verweyi host using mitochondrial and nuclear markers showed no genetic differentiation among sites. Changes in the composition of Symbiodinium types associated with P. verweyi among closely located sites in Kenting suggested that this coral might have acclimatized to the constant thermal stress by selective association with heat‐tolerant Symbiodinium types, whereas the role of the host in adaptation was inconclusive.

Oceanicaulis stylophorae sp. nov., isolated from the reef-building coral Stylophora pistillata.

A bacterial strain, designated KTW-16(T), was isolated from the reef-building coral Stylophora pistillata, collected from southern Taiwan. Strain KTW-16(T) was a Gram-negative, facultatively anaerobic, pale-yellow, non-motile short rod. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain KTW-16(T) belonged to the genus Paracoccus in the Alphaproteobacteria and exhibited 93.7-96.9 % 16S rRNA gene sequence similarity with type strains of species of the genus Paracoccus (96.9 % with Paracoccus alcaliphilus JCM 7364(T)). Strain KTW-16(T) grew at 15-40 °C (optimum 35 °C), at pH 6.0-10.0 (optimum pH 8.0) and with 0-9 % NaCl (optimum 5 %). The predominant cellular fatty acids were C₁₈:₁ω7c, C₁₉:₀ cyclo ω8c and C₁₈:₀. The major respiratory quinone was Q-10 and the DNA G+C content was 69.1 mol%. The polar lipid profile consisted of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine and several unknown polar lipids. The physiological and biochemical tests allowed clear phenotypic differentiation of the isolate from the type strains of already described Paracoccus species. It is evident from the genotypic, phenotypic and chemotaxonomic analysis that strain KTW-16(T) should be classified in a novel species of the genus Paracoccus, for which the name Paracoccus stylophorae sp. nov. is proposed. The type strain is KTW-16(T) ( = LMG 25392(T)  = BCRC 80106(T)).

Can resistant coral-Symbiodinium associations enable coral communities to survive climate change? A study of a site exposed to long-term hot water input

Climate change has led to a decline in the health of corals and coral reefs around the world. Studies have shown that, while some corals can cope with natural and anthropogenic stressors either through resistance mechanisms of coral hosts or through sustainable relationships with Symbiodinium clades or types, many coral species cannot. Here, we show that the corals present in a reef in southern Taiwan, and exposed to long-term elevated seawater temperatures due to the presence of a nuclear power plant outlet (NPP OL), are unique in terms of species and associated Symbiodinium types. At shallow depths (<3 m), eleven coral genera elsewhere in Kenting predominantly found with Symbiodinium types C1 and C3 (stress sensitive) were instead hosting Symbiodinium type D1a (stress tolerant) or a mixture of Symbiodinium type C1/C3/C21a/C15 and Symbiodinium type D1a. Of the 16 coral genera that dominate the local reefs, two that are apparently unable to associate with Symbiodinium type D1a are not present at NPP OL at depths of <3 m. Two other genera present at NPP OL and other locations host a specific type of Symbiodinium type C15. These data imply that coral assemblages may have the capacity to maintain their presence at the generic level against long-term disturbances such as elevated seawater temperatures by acclimatization through successful association with a stress-tolerant Symbiodinium over time. However, at the community level it comes at the cost of some coral genera being lost, suggesting that species unable to associate with a stress-tolerant Symbiodinium are likely to become extinct locally and unfavorable shifts in coral communities are likely to occur under the impact of climate change.

Paracoccus isoporae sp. nov., isolated from the reef-building coral Isopora palifera.

A bacterial strain, designated SW-3(T), was isolated from the reef-building coral Isopora palifera, from Southern Taiwan, and was characterized by using a polyphasic taxonomic approach. Cells of strain SW-3(T) were Gram-reaction-negative, aerobic, rod-shaped and motile by means of monopolar flagella and formed cream-white colonies. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain SW-3(T) belonged to the genus Paracoccus and its most closely related neighbours were P. aestuarii B7(T), P. homiensis DD-R11(T), P. marinus KKL-A5(T), P. denitrificans DSM 413(T) and P. zeaxanthinifaciens R-1512(T), with sequence similarities of 96.8, 96.6, 96.1, 95.8 and 94.9 %, respectively. Strain SW-3(T) exhibited optimal growth at 25-30 °C and pH 9-10 and in 3-5 % (w/v) NaCl. The predominant cellular fatty acid was summed feature 8 (C(18 : 1)ω7c and/or C(18 : 1)ω6c; 75 %). The major respiratory quinone was Q-10. The polar lipid profile consisted of a mixture of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine and several uncharacterized polar lipids. The DNA G+C content of strain SW-3(T) was 63.7 mol%. The results of physiological and biochemical tests allowed clear phenotypic differentiation of this isolate from recognized species of the genus Paracoccus. It is evident from the genotypic, phenotypic and chemotaxonomic data that strain SW-3(T) represents a novel species of the genus Paracoccus, for which the name Paracoccus isoporae sp. nov. is proposed. The type strain is SW-3(T) ( = LMG 25205(T)  = BCRC 17967(T)).

Recurrent disturbances and the degradation of hard coral communities in Taiwan.

Recurrent disturbances can have a critical effect on the structure and function of coral reef communities. In this study, long-term changes were examined in the hard coral community at Wanlitung, in southern Taiwan, between 1985 and 2010. In this 26 year interval, the reef has experienced repeated disturbances that include six typhoons and two coral-bleaching events. The frequency of disturbance has meant that species susceptible to disturbance, such as those in the genus Acropora and Montipora have almost disappeared from the reef. Indeed, almost all hard coral species have declined in abundance, with the result that total hard coral cover in 2010 (17.7%) was less than half what it was in 1985 (47.5%). In addition, macro-algal cover has increased from 11.3% in 2003 to 28.5% in 2010. The frequency of disturbance combined with possible chronic influence of a growing human population mean that a diverse reef assemblage is unlikely to persist on this reef into the future.

Pseudoteredinibacter isoporae gen. nov., sp. nov., a marine bacterium isolated from the reef-building coral Isopora palifera.

A Gram-negative, heterotrophic, marine bacterium, designated strain SW-11(T), was isolated from the reef-building coral Isopora palifera in Kenting, Taiwan. Cells were rods and were motile by a single polar flagellum. The strain grew at 10-45 °C (optimum, 30-35 °C), at pH 7.0-8.0 (optimum, pH 7.5) and with 2.0-4.0 % NaCl (optimum, 2.5-3.0 %). The polar lipids comprised phosphatidylethanolamine, phosphatidylglycerol, phosphatidylserine, diphosphatidylglycerol and four unknown phospholipids. Isoprenoid quinones consisted of ubiquinone 9 (78.8 %) and ubiquinone 8 (21.1 %). Major cellular fatty acids were summed feature 3 (C(16 : 1)ω7c and/or C(16 : 1)ω6c; 22.3 %), C(17 : 1)ω8c (13.4 %), summed feature 8 (C(18 : 1)ω6c and/or C(18 : 1)ω7c; 13.1 %), C(16 : 0) (10.3 %) and anteiso-C(17 : 1)ω9c (10.0 %). The DNA G+C content was 51.6 mol%. 16S rRNA gene sequence analysis indicated that strain SW-11(T) belongs to the class Gammaproteobacteria and is a member of the order Alteromonadales. Strain SW-11(T) shared 93.2 % 16S rRNA gene sequence similarity with Teredinibacter turnerae T7902(T) and 92.1 % with Saccharophagus degradans 2-40(T), and can be further distinguished from these two related strains by distinct patterns of fatty acid content and differences in the polar lipid profile, the ability to utilize different compounds as carbon sources, the ability to degrade various compounds and differences in enzyme activities. The phylogenetic data and those from physiological, morphological and chemotaxonomic characterizations indicate that strain SW-11(T) represents a novel species and genus, for which the name Pseudoteredinibacter isoporae gen. nov., sp. nov. is proposed. The type strain of Pseudoteredinibacter isoporae is SW-11(T) ( = BCRC 17935(T)  = LMG 25246(T)).

Shimia isoporae sp. nov., isolated from the reef-building coral Isopora palifera.

A bacterial strain, designated SW6(T), was isolated from the reef-building coral Isopora palifera, collected from seawater off the coast of southern Taiwan, and characterized using a polyphasic taxonomic approach. Strain SW6(T) was Gram-negative, aerobic, beige coloured, rod-shaped and motile by monopolar flagella. 16S rRNA gene sequence studies showed that the strain clustered closely with Shimia marina JCM 13038(T) (97.9 % 16S rRNA gene sequence similarity). Strain SW6(T) required NaCl for growth and exhibited optimal growth at 25-30 °C and 3-4 % NaCl. The predominant cellular fatty acid was summed feature 8 (C(18 : 1)ω7c/C(18 : 1)ω6c; 64.1 %). The major respiratory quinone was ubiquinone Q-10 and the DNA G+C content was 54.9 mol%. The results of physiological and biochemical tests allowed clear phenotypic differentiation of this isolate from previously described species of the genus Shimia. It is evident from the genotypic, phenotypic and chemotaxonomic data that the new strain should be classified as a representative of a novel species in the genus Shimia. The name proposed for this taxon is Shimia isoporae sp. nov.; the type strain is SW6(T) ( = LMG 25377(T) = BCRC 80085(T)).