Flavobacterium ahnfeltiae sp. nov., a new marine polysaccharide-degrading bacterium isolated from a Pacific red alga

Influence of vegetation and substrate type on removal of emerging organic contaminants and microbial dynamics in horizontal subsurface constructed wetlands

Constructed wetlands (CWs) offer an efficient alternative technology for removing emerging organic contaminants (EOCs) from wastewater. Optimizing CW performance requires understanding the impact of CW configuration on EOC removal and microbial community dynamics. This study investigated EOC removal and microbial communities in horizontal subsurface flow (HSSF) CWs over a 26-month operational period. Comparison between tuff-filled and gravel-filled CWs highlighted the superior EOC removal in tuff-filled CWs during extended operation, likely caused by the larger surface area of the tuff substrate fostering microbial growth, sorption, and biodegradation. Removal of partially positively charged EOCs, like atenolol (29-98 %) and fexofenadine (21-87 %), remained constant in the different CWs, and was mainly attributed to sorption. In contrast, removal rates for polar non-sorbing compounds, including diclofenac (3-64 %), acyclovir (9-85 %), and artificial sweeteners acesulfame (5-60 %) and saccharin (1-48 %), seemed to increase over time due to enhanced biodegradation. The presence of vegetation and different planting methods (single vs. mixed plantation) had a limited impact, underscoring the dominance of substrate type in the CW performance. Microbial community analysis identified two stages: a startup phase (1-7 months) and a maturation phase (19-26 months). During this transition, highly diverse communities dominated by specific species in the early stages gave way to more evenly distributed and relatively stable communities. Proteobacteria and Bacteroidetes remained dominant throughout. Alphaproteobacteria, Acidobacteria, Planctomycetes, Salinimicrobium, and Sphingomonas were enriched during the maturation phase, potentially serving as bioindicators for EOC removal. In conclusion, this study emphasizes the pivotal role of substrate type and maturation in the removal of EOCs in HSSF CW, considering the complex interplay with EOC physicochemical properties. Insights into microbial community dynamics underscore the importance of taxonomic and functional diversity in assessing CW effectiveness. This knowledge aids in optimizing HSSF CWs for sustainable wastewater treatment, EOC removal, and ecological risk assessment, ultimately contributing to environmental protection.

Bacterioplankton diversity and potential health risks in volcanic lakes: A study from Arxan Geopark, China

Bacterioplankton play a vital role in maintaining the functions and services of lake ecosystems. Understanding the diversity and distribution patterns of bacterioplankton, particularly the presence of potential pathogenic bacterial communities, is crucial for safeguarding human health. In this study, we employed 16S rRNA gene amplicon sequencing to investigate the diversity and geographic patterns of bacterioplankton communities, as well as potential pathogens, in eight volcanic lakes located in the Arxan UNESCO Global Geopark (in the Greater Khingan Mountains of China). Our results revealed that the bacterial communities primarily comprised Bacteroidota (45.3%), Proteobacteria (33.1%), and Actinobacteria (9.0%) at the phylum level. At the genus level, prominent taxa included Flavobacterium (31.5%), Acinetobacter (11.0%), Chryseobacterium (7.9%), and CL500-29 marine group (5.6%). Among the bacterioplankton, we identified 34 pathogen genera (165 amplicon sequence variants [ASVs]), with Acinetobacter (59.8%), Rahnella (18.3%), Brevundimonas (9.6%), and Pseudomonas (5.8%) being the most dominant. Our findings demonstrated distinct biogeographic patterns in the bacterial communities at the local scale, driven by a combination of dispersal limitation and environmental factors influenced by human activities. Notably, approximately 15.3% of the bacterioplankton reads in the Arxan lakes were identified as potential pathogens, underscoring the potential risks to public health in these popular tourist destinations. This study provides the first comprehensive insight into the diversity of bacterioplankton in mountain lake ecosystems affected by high tourist activity, laying the groundwork for effective control measures against bacterial pathogens.

Rhodoalgimonas zhirmunskyi gen. nov., sp. nov., a Marine Alphaproteobacterium Isolated from the Pacific Red Alga Ahnfeltia tobuchiensis: Phenotypic Characterization and Pan-Genome Analysis

A novel Gram-staining negative, strictly aerobic, rod-shaped, and non-motile bacterium, designated strain 10Alg 79T, was isolated from the red alga Ahnfeltia tobuchiensis. A phylogenetic analysis based on 16S rRNA gene sequences placed the novel strain within the family Roseobacteraceae, class Alphaproteobacteria, phylum Pseudomonadota, where the nearest neighbor was Shimia sediminis ZQ172T (97.33% of identity). However, a phylogenomic study clearly showed that strain 10Alg 79T forms a distinct evolutionary lineage at the genus level within the family Roseobacteraceae combining with strains Aquicoccus porphyridii L1 8-17T, Marimonas arenosa KCTC 52189T, and Lentibacter algarum DSM 24677T. The ANI, AAI, and dDDH values between them were 75.63-78.15%, 67.41-73.08%, and 18.8-19.8%, respectively. The genome comprises 3,754,741 bp with a DNA GC content of 62.1 mol%. The prevalent fatty acids of strain 10Alg 79T were C18:1 ω7c and C16:0. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, an unidentified aminolipid, an unidentified phospholipid and an unidentified lipid. A pan-genome analysis showed that the unique part of the 10Alg 79T genome consists of 13 genus-specific clusters and 413 singletons. The annotated singletons were more often related to transport protein systems, transcriptional regulators, and enzymes. A functional annotation of the draft genome sequence revealed that this bacterium could be a source of a new phosphorylase, which may be used for phosphoglycoside synthesis. A combination of the genotypic and phenotypic data showed that the bacterial isolate represents a novel species and a novel genus, for which the name Rhodoalgimonas zhirmunskyi gen. nov., sp. nov. is proposed. The type strain is 10Alg 79T (=KCTC 72611T = KMM 6723T).

Tamlana laminarinivorans sp. nov. and Tamlana sargassicola sp. nov., two novel species isolated from Sargassum, show genomic and physiological adaptations for a Sargassum-associated lifestyle

The genus Tamlana from the Bacteroidota currently includes six validated species. Two strains designated PT2-4T and 62-3T were isolated from Sargassum abundant at the Pingtan island coast in the Fujian Province of China. 16S rRNA gene sequence analysis showed that the closest described relative of strains PT2-4T and 62-3T is Tamlana sedimentorum JCM 19808T with 98.40 and 97.98% sequence similarity, respectively. The 16S rRNA gene sequence similarity between strain PT2-4T and strain 62-3T was 98.68 %. Furthermore, the highest average nucleotide identity values were 87.34 and 88.97 % for strains PT2-4T and 62-3T, respectively. The highest DNA-DNA hybridization (DDH) value of strain PT2-4T was 35.2 % with strain 62-3T, while the DDH value of strain 62-3T was 37.7 % with T. sedimentorum JCM 19808T. Growth of strains PT2-4T and 62-3T occurs at 15-40 °C (optimum, 30 °C) with 0-4 % (w/v) NaCl (optimum 0-1 %). Strains PT2-4T and 62-3T can grow from pH 5.0 to 10.0 (optimum, pH 7.0). The major fatty acids of strains PT2-4T and 62-3T are iso-C15 : 0 and iso G-C15 : 1. MK-6 is the sole respiratory quinone. Genomic and physiological analyses of strains PT2-4T and 62-3T showed corresponding adaptive features. Significant adaptation to the growth environment of macroalgae includes the degradation of brown algae-derived diverse polysaccharides (alginate, laminarin and fucoidan). Notably, strain PT2-4T can utilize laminarin, fucoidan and alginate via specific carbohydrate-active enzymes encoded in polysaccharide utilization loci, rarely described for the genus Tamlana to date. Based on their distinct physiological characteristics and the traits of utilizing polysaccharides from Sargassum, strains PT2-4T and 62-3T are suggested to be classified into two novel species, Tamlana laminarinivorans sp. nov. and Tamlana sargassicola sp. nov. (type strain PT2-4T=MCCC 1K04427T=KCTC 92183T and type strain 62-3T=MCCC 1K04421T=KCTC 92182T).

What lies on macroalgal surface: diversity of polysaccharide degraders in culturable epiphytic bacteria

Macroalgal surface constitutes a peculiar ecological niche and an advantageous substratum for microorganisms able to degrade the wide diversity of algal glycans. The degrading enzymatic activities of macroalgal epiphytes are of paramount interest for the industrial by-product sector and biomass resource applications. We characterized the polysaccharide hydrolytic profile of bacterial isolates obtained from three macroalgal species: the red macroalgae Asparagopsis taxiformis and Sphaerococcus coronopifolius (Rhodophyceae) and the brown Halopteris scoparia (Phaeophyceae), sampled in South Portugal. Bacterial enrichment cultures supplemented with chlorinated aliphatic compounds, typically released by marine algae, were established using as inoculum the decaying biomass of the three macroalgae, obtaining a collection of 634 bacterial strains. Although collected from the same site and exposed to the same seawater seeding microbiota, macroalgal cultivable bacterial communities in terms of functional and phylogenetic diversity showed host specificity. Isolates were tested for the hydrolysis of starch, pectin, alginate and agar, exhibiting a different hydrolytic potential according to their host: A. taxiformis showed the highest percentage of active isolates (91%), followed by S. coronopifolius (54%) and H. scoparia (46%). Only 30% of the isolates were able to degrade starch, while the other polymers were degraded by 55-58% of the isolates. Interestingly, several isolates showed promiscuous capacities to hydrolyze more than one polysaccharide. The isolate functional fingerprint was statistically correlated to bacterial phylogeny, host species and enrichment medium. In conclusion, this work depicts macroalgae as holobionts with an associated microbiota of interest for blue biotechnologies, suggesting isolation strategies and bacterial targets for polysaccharidases' discovery.

Flavobacterium selenitireducens sp. nov., isolated from rhizosphere soil of ancient mulberry

A Gram-stain-negative, non-motile, aerobic, yellow, convex, rod-shaped mesophilic bacterial strain, designated strain D33T, was isolated from rhizosphere soil of ancient mulberry in Dezhou city, Shandong province, PR China. The strain grew at 8–37 °C (optimum, 30 °C), pH 4–9 (optimum, pH 7) and growth occurred at 0.5–5.5 % (w/v) NaCl (optimally at 1 %). The results of the phylogenetic analyses of 16S rRNA gene and whole genome sequences indicated that D33T was closely related to members of the genus Flavobacterium and had the highest 16S rRNA gene sequence similarity with ‘Flavobacterium agri’ KACC 19300 (95.4 %), Flavobacterium ichthyis NST-5T (94.6 %), Flavobacterium ahnfeltiae KCTC 32467T (93.6 %) and Flavobacterium longum JCM 19141T (93.6 %). The genome size of D33T was 3.8 Mb and the DNA G+C content was 48.0 mol%. The average nucleotide identity (ANI), digital DNA–DNA hybridization (dDDH) and average amino acid identity (AAI) values among D33T and reference strains were lower than the threshold values for species delineation. The only respiratory quinone of D33T was menaquinone 6 (MK-6). The predominant fatty acids (>5 %) were C15:0, C16 : 0, C18 : 0, iso-C15:0, iso–C17 : 0 3-OH, anteiso-C15 : 0 and summed feature 9 . The polar lipid profile contained phosphatidylethanolamine, two unidentified aminophospholipids, three unidentified aminolipids and two unidentified lipids. Combined data from phenotypic, phylogenetic and chemotaxonomic studies indicated that D33T is a representative of a novel species of the genus Flavobacterium, for which the name Flavobacterium selenitireducens sp. nov. is proposed. The type strain is D33T (=GDMCC 1.1946T=KACC 22131T).

Discovery and characterization of a novel α-l-fucosidase from the marine-derived Flavobacterium algicola and its application in 2'-fucosyllactose production

2'-Fucosyllactose (2'-FL) is one of the nutrient ingredients in human milk, which has various beneficial health effects. α-l-fucosidase is a biotechnological tool for 2'-FL preparation. Here, a novel and efficient α-l-fucosidase OUC-Jdch16 from the fucoidan-digesting strain Flavobacterium algicola 12076 was heterologously expressed and applied to produce 2'-FL in vitro. OUC-Jdch16 belongs to glycoside hydrolases (GH) family 29 and exhibits the highest 4-nitrophenyl-α-l-fucopyranoside-hydrolyzing activity at 25 °C and pH 6.0. OUC-Jdch16 could catalyze the synthesis of 2'-FL via transferring the fucosyl residue from pNP-α-fucose to lactose. Under the optimal transfucosylation conditions, the yield of the transfucosylation product reached 84.82% and 92.15% (mol/mol) from pNP-α-fucose within 48 h and 120 h, respectively. Moreover, OUC-Jdch16 was capable of transferring the fucosyl residue to other glycosyl receptors with the generation of novel fucosylated compounds. This study demonstrated that OUC-Jdch16 could be a promising tool to prepare 2'-FL and other novel glycosides.

Aureibaculum algae sp. nov. isolated from the Pacific red alga Ahnfeltia tobuchiensis

A Gram stain-negative, aerobic, rod-shaped, motile by gliding and yellow-orange-pigmented bacterium, designated strain 10Alg 115^T, was isolated from the red alga Ahnfeltia tobuchiensis. The phylogenetic analysis based on 16S rRNA gene sequences placed the novel strain within the family Flavobacteriaceae, phylum Bacteroidetes. The nearest neighbor of the new isolate was Aureibaculum marinum KCTC 62204^T with sequence similarity of 98.1%. The average nucleotide similarity and digital DNA-DNA hybridization values between the novel strain and Aureibaculum marinum KCTC 62204^T were 80% and 22.3%, respectively. The prevalent fatty acids of strain 10Alg 115^T were iso-C_15:0, iso-C_15:1 G_, iso-C_17:0 3-OH, iso-C_16:0 3-OH and C_15:0. The polar lipid profile consisted of phosphatidylethanolamine, two unidentified aminolipids and two unidentified lipids. The DNA G + C content of the type strain calculated from the whole-genome sequence was 32.2 mol%. A combination of the genotypic and phenotypic data showed that the algal isolate represents a novel species of the of genus Aureibaculum, for which the name Aureibaculum algae sp. nov. is proposed. The type strain is 10Alg 115^T (= KCTC 62086^T = KMM 6764^T).

Common Environmental Pollutants Negatively Affect Development and Regeneration in the Sea Anemone Nematostella vectensis Holobiont

The anthozoan sea anemone Nematostella vectensis belongs to the phylum of cnidarians which also includes jellyfish and corals. Nematostella are native to United States East Coast marsh lands, where they constantly adapt to changes in salinity, temperature, oxygen concentration and pH. Its natural ability to continually acclimate to changing environments coupled with its genetic tractability render Nematostella a powerful model organism in which to study the effects of common pollutants on the natural development of these animals. Potassium nitrate, commonly used in fertilizers, and Phthalates, a component of plastics are frequent environmental stressors found in coastal and marsh waters. Here we present data showing how early exposure to these pollutants lead to dramatic defects in development of the embryos and eventual mortality possibly due to defects in feeding ability. Additionally, we examined the microbiome of the animals and identified shifts in the microbial community that correlated with the type of water that was used to grow the animals, and with their exposure to pollutants.

Bacterial diversity, community composition and metabolic function in Lake Tianmuhu and its dammed river: Effects of domestic wastewater and damming

Anthropogenic disturbances, such as pollution discharge and damming, can lead to a global decline in biodiversity in aquatic ecosystems. However, how such disturbances affect microbial community composition and function remains poorly understood. In November 2019, we explored bacterial diversity, community composition and metabolic function in Lake Tianmuhu, China, and in its upstream dammed river, using Illumina MiSeq sequencing and Biolog EcoPlate method based on carbon source utilization. Our results revealed higher variations in bacterial α- and β-diversity in the dammed river ecosystem than in the lake ecosystem. In addition, the dammed river and lake ecosystems were significantly different in bacterial community compositions and metabolic structures. No significant relationship between species richness and functional (metabolic) diversity was observed in this study. The site that was most impacted by domestic wastewater had the lowest taxonomic diversity but highest metabolic capacity and activity, suggesting that community composition rather than species diversity is more important in determining ecosystem functioning. Overall, our findings indicate that anthropogenic disturbances can significantly alter bacterial community and function, and taxonomic diversity is a weak proxy for ecosystem functioning in a natural freshwater habitat.

Flavobacterium profundi sp. nov., isolated from a deep-sea seamount

The Gram-stain-negative, rod-shaped, facultative anaerobic, motile bacterial strain, designated TP390^T, was isolated from a seamount near the Yap Trench in the tropical western Pacific. Phylogenetic analysis based on 16S rRNA gene sequence showed that strain TP390^T was related to the genus Flavobacterium and had highest 16S rRNA gene sequence identity with the type strain of Flavobacterium jejuense EC11^T (97.8 %). Sequence similarities to all other type strains of current species of the genus Flavobacterium were below 97 %. The predominant cellular fatty acids were iso-C_15 : 0 and iso-C_15 : 1G. The quinone system for strain TP390^T comprised predominantly menaquinone MK-6 and the polar lipid profile contained phosphatidylethanolamine, four unknown aminolipids, one glycolipid and six unknown polar lipids. The genomic DNA G+C content of strain TP390^T was 31.2 mol%. In addition, the maximum values of in silico DNA-DNA hybridization (isDDH) and average nucleotide identity (ANI) between strain TP390^T with F. jejuense KCTC 42149^T were 22.60 and 80.01% respectively. Combined data from phenotypic, phylogenetic, isDDH and ANI data demonstrated that the strain TP390^T is representative of a novel species of the genus Flavobacterium, for which we propose the name Flavobacterium profundi sp. nov. (type strain TP390^T=KACC 18559^T=CGMCC 1.15398^T).

Flavobacterium alkalisoli sp. nov., isolated from rhizosphere soil of Suaeda salsa

A Gram-negative, strictly aerobic, gliding motility, none-spore forming, yellow, rods bacterial strain, designated XS-5T, was isolated from rhizosphere soil of Suaeda salsa, in Tumd Right Banner, Inner Mongolia, PR China. A phylogenetic tree based on the 16S rRNA gene sequences and the phylogenomic tree both showed that strain XS-5T clustered with Flavobacterium beibuense F44-8T (shared 97.2 % of 16S rRNA gene similarity) and Flavobacterium rakeshii FCS-5T (97.6 %), and shared <96.0 % of 16S rRNA gene similarities with all other type strains. Strain XS-5T contained MK-6 as the major respiratory quinone. Its major polar lipids were phosphatidylethanolamine, an unidentified aminolipid and an unidentified lipid; and the major fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH, C16 : 0, iso-C15 : 0 3-OH, Summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1  ω7c), and Summed feature 9 (iso-C17 : 1  ω9c and/or C16 : 0 10-methyl). The genome consisted of a 3 985 855 bp circular chromosome, with a G+C content of 37.9 mol%, predicting 3616 coding sequences genes, 45 tRNA genes and three rRNA operons. The average nucleotide identity, amino acid identity and digital DNA–DNA hybridization values of strain XS-5T to F. beibuense F44-8T and F. rakeshii FCS-5T were 79.2 and 79.2 %, 81.7 and 81.6 %, 22.3 and 22.2 %, respectively. The results of phylogenetic, physiological and biochemical tests allowed the discrimination of strain XS-5T from its phylogenetic relatives. Flavobacterium alkalisoli sp. nov. is therefore proposed with strain XS-5T (=CGMCC 1.17077T=KCTC 72459T) as the type strain.

The influence mechanism of bioclogging on pollution removal efficiency of vertical flow constructed wetland

The effect of change of hydraulic characteristic and microbial community on pollution removal efficiency of the infiltration systems in the bioclogging development process remain poorly understood. In this study, therefore, the pollutant removal as a response to hydraulic conductivity reduction and the change of diversity and structure of microbial communities in vertical flow constructed wetlands (VFCWs) was investigated. The results indicated that the richness and diversity of the bacterial communities in the columns at different depths were decreased, and the microbial communities of the genus level were changed in the process of bioclogging. However, the variation of microbial communities has a low impact on the purification performance of VFCWs because the abundance of function groups, respiratory activity, and degradation potentiality of microorganisms remain steady or even get improved in the columns after bioclogging. On the contrary, the hydraulic efficiency of VFCWs decreased greatly by 16.9%, 9.9%, and 57.1% for VFCWs filled with zeolite (Column I), gravel (Column II), and ceramsite (Column III), respectively. The existence of short-circuiting and dead zones in the filter media cause the poor pollution removal efficiency of VFCWs due to the short contact time and decrease of oxygenation renewal, as well as low activity in the dead zone.

Feasibility of isolated novel facultative quorum quenching consortiums for fouling control in an AnMBR

Anaerobic membrane bioreactor (AnMBR) technology is being recognized as an appealing strategy for wastewater treatment, however, severity of membrane fouling inhibits its widespread implementations. This study engineered novel facultative quorum quenching consortiums (FQQs) coping with membrane fouling in AnMBRs with preliminary analysis for their quorum quenching (QQ) performances. Herein, Acyl-homoserine lactones (AHLs)-based quorum sensing (QS) in a lab-scale AnMBR initially revealed that N-Hexanoyl-dl-homoserine lactone (C6-HSL), N-Octanoyl-dl-homoserine lactone (C8-HSL) and N-Decanoyl-dl-homoserine lactone (C10-HSL) were the dominant AHLs in AnMBRs in this study. Three FQQs, namely, FQQ-C6, FQQ-C8 and FQQ-C10, were harvested after anaerobic screening of aerobic QQ consortiums (AeQQs) which were isolated by enrichment culture, aiming to degrade C6-HSL, C8-HSL and C10-HSL, respectively. Growth of FQQ-C6 and FQQ-C10 using AHLs as carbon source under anaerobic condition was significantly faster than those using acetate, congruously suggesting that their QQ performance will not be compromised in AnMBRs. All FQQs degraded a wide range of AHLs pinpointing their extensive QQ ability. FQQ-C6, FQQ-C8 and FQQ-C10 remarkably alleviated extracellular polymeric substances (EPS) production in a lab-scale AnMBR by 72.46%, 35.89% and 65.88%, respectively, and FQQ-C6 retarded membrane fouling of the AnMBR by 2 times. Bioinformatics analysis indicated that there was a major shift in dominant species from AeQQs to FQQs where Comamonas sp., Klebsiella sp., Stenotrophomonas sp. and Ochrobactrum sp. survived after anaerobic screening and were the majority in FQQs. High growth rate utilizing AHLs under anaerobic condition and enormous EPS retardation efficiency in FQQ-C6 and FQQ-C10 could be attributed to Comamonas sp.. These findings demonstrated that FQQs could be leveraged for QQ under anaerobic systems. We believe that this was the first work proposing a bacterial pool of facultative QQ candidates holding biotechnological promises for membrane fouling control in AnMBRs.

Ulvibacterium marinum gen. nov., sp. nov., a novel marine bacterium of the family Flavobacteriaceae, isolated from a culture of the green alga Ulva prolifera

A Gram-stain negative, aerobic, rod-shaped, and non-motile bacterium, designated strain CCMM003^T, was isolated from a culture of the green alga Ulva prolifera. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain CCMM003^T belongs to the family Flavobacteriaceae and exhibits a close relationship to Pseudozobellia thermophila DSM 19858^T (92.5%). Optimal growth occurred in the presence of 4% (w/v) NaCl, at pH 7.0 and 30 °C. The polar lipids of strain CCMM003^T consisted of phosphatidylethanolamine and six unidentified lipids. The predominant isoprenoid quinone was MK-6. The major fatty acids were iso-C_15:0, iso-C_15:1 G, iso-C_17:0 3-OH and summed feature 3 (C_16:1ω7c and/or iso-C_15:0 2-OH). The DNA G + C content of strain CCMM003^T calculated on the basis of the genome sequence was 41.2 mol% and the genome size was 5.9 Mbp. On the basis of data from this polyphasic study, strain CCMM003^T is considered to represent a novel genus and species of the family Flavobacteriaceae, for which the name Ulvibacterium marinum gen. nov., sp. nov. is proposed. The type strain is CCMM003^T (= MCCC 1K03244^T =KCTC 52639^T).

Zunongwangia flava sp. nov., belonging to the family Flavobacteriaceae, isolated from Salicornia europaea

A yellow pigmented bacterium designated strain MBLN094^T within the family Flavobacteriaceae was isolated from a halophyte Salicornia europaea on the coast of the Yellow Sea. This strain was a Gram-stain negative, aerobic, non-spore forming, rod-shaped bacterium. Phylogenetic analysis of the 16S rRNA gene sequence of strain MBLN094^T was found to be related to the genus Zunongwangia, exhibiting 16S rRNA gene sequence similarity values of 97.0, 96.8, 96.4, and 96.3% to Zunongwangia mangrovi P2E16^T, Z. profunda SM-A87^T, Z. atlantica 22II14-10F7^T, and Z. endophytica CPA58^T, respectively. Strain MBLN094^T grew at 20‒37°C (optimum, 25‒30°C), at pH 6.0‒10.0 (optimum, 7.0‒8.0), and with 0.5‒15.0% (w/v) NaCl (optimum, 2.0‒5.0%). Menaquinone MK-6 was the sole respiratory quinone. The polar lipids were phosphatidylethanolamine, two unidentified aminolipids, and four unidentified lipids. Major fatty acids were iso-C_17:0 3-OH, summed feature 3 (C_16:1ω6c and/or C16:1 ω7c), and iso-C_15:0. The genomic DNA G + C content was 37.4 mol%. Based on these polyphasic taxonomic data, strain MBLN094^T is considered to represent a novel species of the genus Zunongwangia, for which the name Zunongwangia flava sp. nov. is proposed. The type strain is MBLN094^T (= KCTC 62279^T = JCM 32262^T).

Biotechnology Potential of Marine Fungi Degrading Plant and Algae Polymeric Substrates

Filamentous fungi possess the metabolic capacity to degrade environment organic matter, much of which is the plant and algae material enriched with the cell wall carbohydrates and polyphenol complexes that frequently can be assimilated by only marine fungi. As the most renewable energy feedstock on the Earth, the plant or algae polymeric substrates induce an expression of microbial extracellular enzymes that catalyze their cleaving up to the component sugars. However, the question of what the marine fungi contributes to the plant and algae material biotransformation processes has yet to be highlighted sufficiently. In this review, we summarized the potential of marine fungi alternatively to terrestrial fungi to produce the biotechnologically valuable extracellular enzymes in response to the plant and macroalgae polymeric substrates as sources of carbon for their bioconversion used for industries and bioremediation.

Flavobacterium zaozhuangense sp. nov., a new member of the family Flavobacteriaceae, isolated from metolachlor-contaminated soil

Strain ZZ-8^T, a Gram-negative, aerobic, non-spore-forming, non-motile, yellow-pigmented, rod-shaped bacterium, was isolated from metolachlor-contaminated soil in China. The taxonomic position was investigated using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain ZZ-8^T is a member of the genus Flavobacterium and shows high sequence similarity to Flavobacterium humicola UCM-46^T (97.2%) and Flavobacterium pedocola UCM-R36^T (97.1%), and lower (< 97%) sequence similarity to other known Flavobacterium species. Chemotaxonomic analysis revealed that strain ZZ-8^T possessed MK-6 as the major respiratory quinone; and iso-C_15:0 (28.5%), summed feature 9 (iso-C_17:1 w9c/C_16:0 10-methyl, 22.9%), iso-C_17:0 3-OH (17.0%), iso-C_15:0 3-OH (8.9%), iso-C_15:1 G (8.6%) and summed feature 3 (C_16:1 w7c/C_16:1 w6c, 5.7%) as the predominant fatty acids. The polar lipids of strain ZZ-8^T were determined to be lipids, a glycolipid, aminolipids and phosphatidylethanolamine. Strain ZZ-8^T showed low DNA-DNA relatedness with F. pedocola UCM-R36^T (43.23 ± 4.1%) and F. humicola UCM-46^T (29.17 ± 3.8%). The DNA G+C content was 43.3 mol%. Based on the phylogenetic and phenotypic characteristics, chemotaxonomic data and DNA-DNA hybridization, strain ZZ-8^T is considered a novel species of the genus Flavobacterium, for which the name Flavobacterium zaozhuangense sp. nov. (type strain ZZ-8^T = KCTC 62315 ^T = CCTCC AB 2017243^T) is proposed.

Association between degradation of pharmaceuticals and endocrine-disrupting compounds and microbial communities along a treated wastewater effluent gradient in Lake Mead

The role of microbial communities in the degradation of trace organic contaminants in the environment is little understood. In this study, the biotransformation potential of 27 pharmaceuticals and endocrine-disrupting compounds was examined in parallel with a characterization of the native microbial community in water samples from four sites variously impacted by urban run-off and wastewater discharge in Lake Mead, Nevada and Arizona, USA. Samples included relatively pristine Colorado River water at the upper end of the lake, nearly pure tertiary-treated municipal wastewater entering via the Las Vegas Wash, and waters of mixed influence (Las Vegas Bay and Boulder Basin), which represented a gradient of treated wastewater effluent impact. Microbial diversity analysis based on 16S rRNA gene censuses revealed the community at this site to be distinct from the less urban-impacted locations, although all sites were similar in overall diversity and richness. Similarly, Biolog EcoPlate assays demonstrated that the microbial community at Las Vegas Wash was the most metabolically versatile and active. Organic contaminants added as a mixture to laboratory microcosms were more rapidly and completely degraded in the most wastewater-impacted sites (Las Vegas Wash and Las Vegas Bay), with the majority exhibiting shorter half-lives than at the other sites or in a bacteriostatic control. Although the reasons for enhanced degradation capacity in the wastewater-impacted sites remain to be established, these data are consistent with the acclimatization of native microorganisms (either through changes in community structure or metabolic regulation) to effluent-derived trace contaminants. This study suggests that in urban, wastewater-impacted watersheds, prior exposure to organic contaminants fundamentally alters the structure and function of microbial communities, which in turn translates into greater potential for the natural attenuation of these compounds compared to more pristine sites.

Flavobacterium sediminilitoris sp. nov., isolated from a tidal flat

A Gram-stain-negative, facultatively aerobic, motile-by-gliding, non-flagellated and rod-shaped bacterial strain, designated YSM-43^T, was isolated from a tidal flat in Yeosu on the South Sea in the Republic of Korea. Strain YSM-43^T grew optimally at 30 °C and in the presence of 1.0-2.0 % (w/v) NaCl. A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences showed that strain YSM-43^T fell within the clade comprising type strains of Flavobacterium species, clustering with the type strains of Flavobacterium jejuense and Flavobacterium jumunjinense. It exhibited 16S rRNA gene sequence similarity values of 97.20 and 97.15 % to the type strains of F. jejuense and F. jumunjinense, respectively, and of less than 96.59 % to the type strains of the other Flavobacterium species. Strain YSM-43^T contained menaquinone-6 as the predominant menaquinone and iso-C15 : 0, iso-C17 : 0 3-OH, iso-C15 : 1 G and iso-C15 : 0 3-OH as the major fatty acids. The major polar lipids were phosphatidylethanolamine and one unidentified lipid. The DNA G+C content of strain YSM-43^T was 29.8 mol% and its DNA-DNA relatedness values with type strains of F. jejuense and F. jumunjinense were 13 and 11 %, respectively. The differential phenotypic properties, together with the phylogenetic and genetic data, revealed that strain YSM-43^T is separate from other recognized species of the genus Flavobacterium. On the basis of the data presented, strain YSM-43^T is considered to represent a novel species of the genus Flavobacterium, for which the name Flavobacteriumsediminilitoris sp. nov. is proposed. The type strain is YSM-43^T (=KACC 19435^T=KCTC 62142^T=NBRC 113020^T).

New insights into the treatment of realN,N-dimethylacetamide contaminated wastewater using a membrane bioreactor and its membrane fouling implications

Treatment of N,N-dimethylacetamide (DMAC) wastewater is an important step in achieving the sustainable industrial application of DMAC as an organic solvent. This is the first time that treatment of a high concentration of DMAC in real wastewater has been assessed using membrane bioreactor technology. In this study, an anoxic–oxic membrane bioreactor (MBR) was operated over a month to mineralize concentrated DMAC wastewater. Severe membrane fouling occurred during the short-term operation of the MBR as the membrane flux decreased from 11.52 to 5.28 L (m² h)⁻¹. The membrane fouling was aggravated by the increased amount of protein fractions present in the MBR mixed liquor. Moreover, results from the excitation–emission matrix analysis identified tryptophan and other protein-like related substances as the major membrane-fouling components. Furthermore, analysis of the DMAC degradation mechanism via high performance liquid chromatography (HPLC) and ion chromatography (IC) revealed that the major degradation products were ammonium and dimethylamine (DMA). Although the MBR system achieved the steady removal of DMAC and chemical oxygen demand (COD) by up to 98% and 80%, respectively at DMAC₀ ≤ 7548 mg L⁻¹, DMA was found to have accumulated in the treated effluent. Our investigation provides insight into the prospect and challenges of using MBR systems for DMAC wastewater degradation.

Treatment of N,N-dimethylacetamide (DMAC) wastewater is an important step in achieving the sustainable industrial application of DMAC as an organic solvent.

Flavobacterium jejuensis sp. nov., isolated from marine brown alga Ecklonia cava

A bacterial strain, designated EC11(T) was isolated from brown alga Ecklonia cava collected from Jeju Island, Korea. EC11(T) was identified as a Gram-negative, rod-shaped and yellow-pigmented bacterial strain. The strain EC11(T) grew over a temperature range of 10 °C to 30 °C (optimally at 25 °C), and a pH range of 6.0-10.5 (optimally at pH 7.5). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain EC11(T) belongs to the genus Flavobacterium. Strain EC11(T) shared close similarity with Flavobacterium jumunjinense HME7102(T) (96.4%), Flavobacterium dongtanense LW30(T) (95.8%), Flavobacterium haoranii LQY-7(T) (95.3%), and Flavobacterium urocaniciphilum (95.1%). The major fatty acids (> 5%) were iso-C17:0 3-OH (22.4%), iso-C15:0 3-OH (19.0%), C15:0 (12.4%), summed feature 3 (comprising C16:1 ω7c/ C16:1 ω6c; 9.78%), iso-C15:1 G (9.6%), and iso-C16:0 3-OH (9.0%). The DNA G+C content was 28.1 mol% and the strain contained MK-6 as the predominant menaquinone. The major polar lipids were phosphatidylethanolamine, two unknown aminolipids and three unknown polar lipids. Based on phenotypic, chemotaxonomic and phylogenetic analysis, strain EC11T represents a novel species of the Flavobacterium genus, for which the name Flavobacterium jejuensis sp. nov. is proposed. The type strain of F. jejuensis is EC11(T) (=KCTC 42149(T) = JCM 30735(T)).

Influence of substrate type on microbial community structure in vertical-flow constructed wetland treating polluted river water

Microorganisms attached on the surfaces of substrate materials in constructed wetland play crucial roles in the removal of organic and inorganic pollutants. However, the impact of substrate material on wetland microbial community structure remains unclear. Moreover, little is known about microbial community in constructed wetland purifying polluted surface water. In this study, Illumina high-throughput sequencing was applied to profile the spatial variation of microbial communities in three pilot-scale surface water constructed wetlands with different substrate materials (sand, zeolite, and gravel). Bacterial community diversity and structure showed remarkable spatial variation in both sand and zeolite wetland systems, but changed slightly in gravel wetland system. Bacterial community was found to be significantly influenced by wetland substrate type. A number of bacterial groups were detected in wetland systems, including Proteobacteria, Chloroflexi, Bacteroidetes, Acidobacteria, Cyanobacteria, Nitrospirae, Planctomycetes, Actinobacteria, Firmicutes, Chlorobi, Spirochaetae, Gemmatimonadetes, Deferribacteres, OP8, WS3, TA06, and OP3, while Proteobacteria (accounting for 29.1-62.3 %), mainly composed of Alpha-, Beta-, Gamma-, and Deltaproteobacteria, showed the dominance and might contribute to the effective reduction of organic pollutants. In addition, Nitrospira-like microorganisms were abundant in surface water constructed wetlands.

List of new names and new combinations previously effectively, but not validly, published

The purpose of this announcement is to effect the valid publication of the following effectively published new names and new combinations under the procedure described in the Bacteriological Code (1990 Revision). Authors and other individuals wishing to have new names and/or combinations included in future lists should send three copies of the pertinent reprint or photocopies thereof, or an electronic copy of the published paper to the IJSEM Editorial Office for confirmation that all of the other requirements for valid publication have been met. It is also a requirement of IJSEM and the ICSP that authors of new species, new subspecies and new combinations provide evidence that types are deposited in two recognized culture collections in two different countries. It should be noted that the date of valid publication of these new names and combinations is the date of publication of this list, not the date of the original publication of the names and combinations. The authors of the new names and combinations are as given below. Inclusion of a name on these lists validates the publication of the name and thereby makes it available in the nomenclature of prokaryotes. The inclusion of a name on this list is not to be construed as taxonomic acceptance of the taxon to which the name is applied. Indeed, some of these names may, in time, be shown to be synonyms, or the organisms may be transferred to another genus, thus necessitating the creation of a new combination.