Synthesis in vitro of very long chain fatty acids in Vibrio sp. strain ABE-1

The activity of fatty acid synthetase (FAS) from Vibrio sp. strain ABE-1 required the presence of acyl carrier protein and was completely inhibited by thiolactomycin, an inhibitor specific for a type II FAS. These observations indicate that this enzyme is a type II FAS. Analysis by gas-liquid chromotography of the reaction products synthesized in vitro from [2-¹⁴C]malonyl-CoA by the partially purified FAS revealed, in addition to 16-and 18-carbon fatty acids which are normal constituents of this bacterium, the presence of fatty acids with very long chains. These fatty acids were identified as saturated and mono-unsaturated fatty acids with 20 up to as many as 30 carbon atoms. The longest fatty acids normally found in this bacterium contain 18-carbon atoms. These results suggest that the FAS from Vibrio sp. strain ABE-1 has potentially the ability to synthesize fatty acids with very long chains.Abbreviations ACP acyl carrier protein - FAME fatty acid methyl ester - FAS fatty acid synthetase - FID flame ionization detection - GLC gas-liquid chromatography - TLC thin-layer chromatography - In designations of fatty acids, such as 16:0, 16:1, etc the colon separates the number that denotes the number of carbon atoms and the number that denotes the number of double bonds, respectively, in the molecule - 16:0-CoA CoA ester of 16:0     

A trans-unsaturated fatty acid in a psychrophilic bacterium, Vibrio sp. strain ABE-1.

A high level of a trans-unsaturated fatty acid was found in the phospholipids of a psychrophilic bacterium, Vibrio sp. strain ABE-1. This fatty acid was identified as 9-trans-hexadecenoic acid (C16:19t) by gas-liquid chromatography and infrared absorption spectrometry. C16:1(9)t accounted for less than 1% of the total fatty acids in cells grown at 5 degrees C and reached 12% of the total at 20 degrees C. We suggest that the increase in the level of the trans-unsaturated fatty acid is related to the high growth rate of this bacterium at elevated temperatures. Possible biological roles of the trans-unsaturated fatty acid in the adaptation of the microorganism to the ambient temperature are discussed.     

Mechanism of biosynthesis of unsaturated fatty acids in Pseudomonas sp. strain E-3, a psychrotrophic bacterium.

Biosynthesis of palmitic, palmitoleic, and cis-vaccenic acids in Pseudomonas sp. strain E-3 was investigated with in vitro and in vivo systems. [1-14C]palmitic acid was aerobically converted to palmitoleate and cis-vaccenate, and the radioactivities on their carboxyl carbons were 100 and 43%, respectively, of the total radioactivity in the fatty acids. Palmitoyl coenzyme A desaturase activity was found in the membrane fraction. [1-14C]stearic acid was converted to octadecenoate and C16 fatty acids. The octadecenoate contained oleate and cis-vaccenate, but only oleate was produced in the presence of cerulenin. [1-14C]lauric acid was aerobically converted to palmitate, palmitoleate, and cis-vaccenate. Under anaerobic conditions, palmitate (62%), palmitoleate (4%), and cis-vaccenate (34%) were produced from [1-14C]acetic acid, while they amounted to 48, 39, and 14%, respectively, under aerobic conditions. In these incorporation experiments, 3 to 19% of the added radioactivity was detected in released 14CO2, indicating that part of the added fatty acids were oxidatively decomposed. Partially purified fatty acid synthetase produced saturated and unsaturated fatty acids with chain lengths of C10 to C18. These results indicated that both aerobic and anaerobic mechanisms for the synthesis of unsaturated fatty acid are operating in this bacterium.     

Microsomal fatty acid desaturation and elongation in a human lung carcinoma grown in nude mice

Since tumor cells show abnormal fatty acid composition, it is likely that their desaturase systems were affected to some extent. Although desaturase activities in experimental tumors have been evaluated, to our knowledge, fatty acid desaturases in human neoplasms and particularly in human tumors grown in nude mice have not been assessed yet. We have therefore, chosen a rapidly growing human lung mucoepidermoid carcinoma (HLMC) grown in nude mice to study microsomal fatty acid desaturation and chain elongation activities. Tumor microsomal proteins were incubated with unlabeled malonyl-CoA and one of the following fatty acids: [1-14C]palmitic (16:0), [1-14C]linoleic (18:2), alpha-[1-14C]linolenic (alpha-18:3), and unlabeled gamma-linolenic (gamma-18:3) plus [2-14C]malonyl-CoA. Data show that HLMC microsomes were capable to desaturate 16:0, alpha-18:3, and dihomogammalinolenic acids (20:3) by delta 9, delta 6 and delta 5 desaturase, respectively; however, delta 6 desaturase activity on [14C]18:2 was not detected. The microsomal elongation system was active in all fatty acid series tested except for 18:2. These findings show that the undetectable activity for 18:2 desaturation is not exclusively found in experimental tumors.     

A multifunctional acyl-acyl carrier protein desaturase from Hedera helix L. (English ivy) can synthesize 16- and 18-carbon monoene and diene products

A desaturase with 83% sequence identity to the coriander delta(4)-16:0-ACP desaturase was isolated from developing seeds of Hedera helix (English ivy). Expression of the ivy desaturase in Arabidopsis resulted in the accumulation of 16:1delta(4) and its expected elongation product 18:1delta(6) (petroselinic acid). Expression in Escherichia coli resulted in the accumulation of soluble, active protein that was purified to apparent homogeneity. In vitro assays confirmed delta(4) desaturation with 16:0-ACP; however, with 18:0-acyl acyl carrier protein (ACP) desaturation occurred at the delta(9) position. The ivy desaturase also converted 16:1delta(9)-ACP and 18:1delta(9)-ACP to the corresponding delta(4,9) dienes. These data suggest at least two distinct substrate binding modes, one placing C4 at the diiron active site and the other placing C9 at the active site. In the latter case, 18:0 would likely bind in an extended conformation as described for the castor desaturase with 9-carbons accommodated in the cavity beyond the dirron site. However, delta(4) desaturation would require the accommodation of 12 carbons for C16 substrates or 14 carbons for C18 substrates. The amino acids lining the substrate binding cavity of ivy and castor desaturases are conserved except for T117R and P179I (castor/ivy). Paradoxically, both substitutions, when introduced into the castor desaturase, favored the binding of shorter acyl chains. Thus, it seems likely that delta(4) desaturation would require a non-extended, perhaps U-shaped, substrate conformation. A cis double bond may facilitate the initiation of such a non-extended conformation in the monounsaturated substrates. The multifunctional properties of the ivy desaturase make it well suited for further dissection of the determinants of regiospecificity.     

Significance and taxonomic value of iso and anteiso monoenoic fatty acids and branded beta-hydroxy acids in Desulfovibrio desulfuricans.

The fatty acids obtained from extractable lipids of the anaerobic sulfate bacterium Desulfovibrio desulfuricans were identified. Saturated and monoenoic iso (C15-C19) and anteiso (C15, C17) fatty acids and saturated normal (C14-C18) and monoenoic normal (C16, C18) fatty acids were shown to be shown to be present by capillary gas chromatography-mass spectrometry. Iso and anteiso beta-hydroxy fatty acids were analyzed as trimethylsilyl ethers in the same way. The position of methyl branches in the monoenoic fatty acids was determined from characteristic fragment ions in the mass spectra of their methyl esters. Disilyloxy methyl esters, prepared by derivatization of the mono unsaturated methyl esters and analyzed by capillary gas chromatography-mass spectrometry, provided the position of double bonds. The monoenoic fatty acids identified in this way were normal (delta7-C16:1, delta9-C16:1, delta9-C18:1, delta11-C18:1), iso (delta7-C15:1, delta9-C16:1, delta9-C17:1, delta11-C18:1, delta11-C19:1), and anteiso (delta7-C15:1, delta9-C17:1). Iso delta9-C17:1 fatty acid is present as the major component. The occurrence of these monoenoic fatty acids in this bacterium is of taxonomical importance.     

Endozoicomonas elysicola gen. nov., sp. nov., a gamma-proteobacterium isolated from the sea slug Elysia ornata

A Gram-negative, strictly aerobic, rod-formed bacterium, strain MKT110(T), was isolated from a mollusk, the sea slug Elysia ornata collected in seawater off the coast of Izu-Miyake Island, Japan at a depth of 15m. Comparative 16S rRNA gene sequences analysis indicated that the isolate MKT110(T) constituted a novel lineage in gamma-proteobacteria related to the genera Zooshikella, Oceanospirillum, Microbulbifer, Marinobacter, Saccharospirillum and Pseudomonas. The strain MKT110(T) was closely related to the clones from marine sponge Halichondria okadai (AB054136, AB054161) and the coral Pocillopora damicornis (AY700600, AY700601). The phylogenetic tree based on the 16S rRNA gene sequences showed that MKT110(T) and four clones formed a sub-lineage related to the genus Zooshikella, with a bootstrap value of 100%. MKT110(T) required salt for its growth and was mesophilic. The bacterium contained 16:1omega7c, 16:0 and 14:0 as major cellular fatty acids, and 3-OH 14:0, 3-OH 10:0 and 3-OH 12:0 as major hydroxy fatty acids. The DNA base composition of the isolate was 50.4 mol% G+C. The major quinone was Q-9. The bacterium is distinguished from currently recognized bacterial genera based on phylogenetic and phenotypic features and should be classified in a novel genus for which the name Endozoicomonas elysicola gen. nov., sp. nov. is proposed. (type strain MKT110(T)=IAM 15107(T)=KCTC 12372(T); GenBank accession no. AB196667).     

Evidence for cis-trans isomerization of a double bond in the fatty acids of the psychrophilic bacterium Vibrio sp. strain ABE-1.

Vibrio sp. strain ABE-1 was grown in a medium that contained as its stable isotope tracer either [2,2-2H2]cis-9-hexadecenoic or [2,2-2H2]trans-9-hexadecenoic acid. Gas chromatographic-mass spectrometric analysis of the cis-9-hexadecenoic and trans-9-hexadecenoic acid fractions from the cells revealed the formation of an intracellularly isomerized 2,2-2H2-fatty acid which differed from the tracer only in the geometrical configuration of the double bond. This observation shows that cis-trans isomerization without a shift in double-bond position between these two geometric hexadecenoic acid isomers can occur in the cells.     

Bacillus algicola sp. nov., a novel filamentous organism isolated from brown alga Fucus evanescens

A slightly yellowish, Gram-positive, filamentous with 'cross-like' branching, aerobic, spore-forming bacterium was isolated from enrichment culture during degradation of the thallus of the brown alga Fucus evanescens. The bacterium studied was chemoorganotrophic, tolerant to 3% NaCl, alkalitolerant, and alginolytic. The predominant cellular fatty acid was ai15:0 which accounted more than 65% of total fatty acids, while i14:0, il5:0 i16:0, and ai17:0 made up 25%. DNA base composition was 37 mol% GC. Phylogenetic analysis of 16S rDNA gene revealed that this isolate was a member of the genus Bacillus, with no close relatives at the species level (16S rRNA gene sequence similarity less 97%). On the basis of the significant differences demonstrated in the phenotypic and chemotaxonomic characteristics, it is suggested that the bacterium be classified as a novel species; the name Bacillus algicola sp. nov. is proposed. The type strain is KMM 3737T (= CIP 107850T).     

Methylopila helvetica sp. nov. and Methylobacterium dichloromethanicum sp. nov.--novel aerobic facultatively methylotrophic bacteria utilizing dichloromethane

Eight strains of Gram-negative, aerobic, asporogenous, neutrophilic, mesophilic, facultatively methylotrophic bacteria are taxonomically described. These icl- serine pathway methylobacteria utilize dichloromethane, methanol and methylamine as well as a variety of polycarbon compounds as the carbon and energy source. The major cellular fatty acids of the non-pigmented strains DM1, DM3, and DM5 to DM9 are C18:1, C16:0, C18:0, Ccy19:0 and that of the pink-pigmented strain DM4 is C18:1. The main quinone of all the strains is Q-10. The non-pigmented strains have similar phenotypic properties and a high level of DNA-DNA relatedness (81-98%) as determined by hybridization. All strains belong to the alpha-subgroup of the alpha-Proteobacteria. 16S rDNA sequence analysis led to the classification of these dichloromethane-utilizers in the genus Methylopila as a new species - Methylopila helvetica sp.nov. with the type strain DM9 (=VKM B-2189). The pink-pigmented strain DM4 belongs to the genus Methylobacterium but differs from the known members of this genus by some phenotypic properties, DNA-DNA relatedness (14-57%) and 16S rDNA sequence. Strain DM4 is named Methylobacterium dichloromethanicum sp. nov. (VKM B-2191 = DSMZ 6343).     

Paenibacillus xylaniclasticus sp. nov., a xylanolytic-cellulolytic bacterium isolated from sludge in an anaerobic digester

A mesophilic, facultative, anaerobic, xylanolytic-cellulolytic bacterium, TW1(T), was isolated from sludge in an anaerobic digester fed with pineapple waste. Cells stained Gram-positive, were spore-forming, and had the morphology of straight to slightly curved rods. Growth was observed in the temperature range of 30 to 50°C (optimum 37°C) and the pH range of 6.0 to 7.5 (optimum pH 7.0) under aerobic and anaerobic conditions. The strain contained meso-diaminopimelic acid in the cell-wall peptidoglycan. The predominant isoprenoid quinone was menaquinone with seven isoprene units (MK-7). Anteiso-C(15:0), iso-C(16:0), anteiso-C(17:0), and C(16:0) were the predominant cellular fatty acids. The G+C content of the DNA was 49.5 mol%. A phylogenetic analysis based on 16S rRNA showed that strain TW1(T) belonged within the genus Paenibacillus and was closely related to Paenibacillus cellulosilyticus LMG 22232(T), P. curdlanolyticus KCTC 3759(T), and P. kobensis KCTC 3761(T) with 97.7, 97.5, and 97.3% sequence similarity, respectively. The DNA-DNA hybridization values between the isolate and type strains of P. cellulosilyticus LMG 22232(T), P. curdlanolyticus KCTC 3759(T), and P. kobensis KCTC 3761(T) were found to be 18.6, 18.3, and 18.0%, respectively. The protein and xylanase patterns of strain TW1(T) were quite different from those of the type strains of closely related Paenibacillus species. On the basis of DNA-DNA relatedness and phenotypic analyses, phylogenetic data and the enzymatic pattern presented in this study, strain TW1(T) should be classified as a novel species of the genus Paenibacillus, for which the name Paenibacillus xylaniclasticus sp. nov. is proposed. The type strain is TW1(T) (=NBRC 106381(T) =KCTC 13719(T) =TISTR 1914(T)).     

Psychrobacter nivimaris sp. nov., a heterotrophic bacterium attached to organic particles isolated from the South Atlantic (Antarctica)

An aggregate-attached bacterium, strain 88/2-7, was isolated from samples of the Southern Ocean and investigated in a polyphasic approach. The novel marine isolate is an aerobic, Gram-negative, oxidase- and catalase-positive, non-motile short rod and grows in form of cream-colored colonies. Growth was observed at 5-35 degrees C. The bacterium tolerated concentrations of 0-13% (w/v) NaCl and utilized a relatively restricted spectrum of carbon sources. The analysis of the fatty acids revealed 18:1 cis 9 (18:1omega9c) as main fatty acid. The G+C content of the DNA was approximately 42 mol%. The sequence of the 16S rDNA assigned strain 88/2-7 to the gamma-subclass of Proteobacteria with a similarity of 99.65% to Psychrobacter proteolyticus (DSM 13887T). A DNA-DNA-hybridization study showed only 26.8% renaturation to the respective strain. Based on the morphological, physiological and molecular properties of the new isolate, the name Psychrobacter nivimaris sp. nov. (type strain 88/2-7T) is proposed.     

Pheromone biosynthetic pathways in the moths Helicoverpa zea and Helicoverpa assulta

Sex pheromones of many Lepidopteran species have relatively simple structures consisting of a hydrocarbon chain with a functional group and usually one to several double bonds. The sex pheromones are usually derived from fatty acids through a specific biosynthetic pathway. We investigated the incorporation of deuterium-labeled palmitic and stearic acid precursors into pheromone components of Helicoverpa zea and Helicoverpa assulta. The major pheromone component for H. zea is (Z)11-hexadecenal (Z11-16:Ald) while H. assulta utilizes (Z)9-hexadecenal (Z9-16:Ald). We found that H. zea uses palmitic acid to form Z11-16:Ald via delta 11 desaturation and reduction, but also requires stearic acid to biosynthesize the minor pheromone components Z9-16:Ald and Z7-16:Ald. The Z9-16:Ald is produced by delta 11 desaturation of stearic acid followed by one round of chain-shortening and reduction to the aldehyde. The Z7-16:Ald is produced by delta 9 desaturation of stearic acid followed by one round of chain-shortening and reduction to the aldehyde. H. assulta uses palmitic acid as a substrate to form Z9-16:Ald, Z11-16:Ald and 16:Ald. The amount of labeling indicated that the delta 9 desaturase is the major desaturase present in the pheromone gland cells of H. assulta; whereas, the delta 11 desaturase is the major desaturase in pheromone glands of H. zea. It also appears that H. assulta lacks chain-shortening enzymes since stearic acid did not label any of the 16-carbon aldehydes.     

Novel psychrophilic anaerobic spore-forming bacterium from the overcooled water brine in permafrost: description Clostridium algoriphilum sp. nov.

A gram-positive, motile, strict anaerobic spore-forming bacterium was isolated from the over-cooled brine in the permafrost. The optimal temperature for isolate growth was 5-6 degrees C at pH 6.8-7.2. The bacterium was growing on the medium rich in saccharides and disaccharides. Out of polysaccharides tested, only xylan sustained the growth. Fermentation of the hexoses led to the formation of acetate, butyrate, lactate, H2,CO2 and some formate and ethanol. Cell wall peptidoglycan contained meso-diaminopimelic acid. The major fatty acids of the cell wall were C(14:0) and C(16:1c9). The content of G-C pairs in DNA was 31.4 mol%. As phylogenetic analysis has shown, it is closely linked to the members of cluster 1 of Clostridium. It differs from the other species of the genus by the substrates necessary for the growth, products forming as a result of the fermentation and content of the fatty acids in the cell wall. Thus, it was suggested to describe this strain as a new species named Clostridium algoriphilum. Type strain 14D1 was deposited into the Russian Collection of the Microorganisms VKM B-2271T and German Collection of the Microorganisms DSM 16153T .     

Vibrio salinus sp. nov., a marine nitrogen-fixing bacterium isolated from the lagoon sediment of an islet inside an atoll in the western Pacific Ocean

A marine, facultatively anaerobic, nitrogen-fixing bacterium, designated strain DNF-1^T, was isolated from the lagoon sediment of Dongsha Island, Taiwan. Cells grown in broth cultures were Gram-negative rods that were motile by means of monotrichous flagella. Cells grown on plate medium produced prosthecae and vesicle-like structures. NaCl was required and optimal growth occurred at about 2–3% NaCl, 25–30 °C and pH 7–8. The strain grew aerobically and was capable of anaerobic growth by fermenting D-glucose or other carbohydrates as substrate. Both the aerobic and anaerobic growth could be achieved with NH₄Cl as a sole nitrogen source. When N₂ served as the sole nitrogen source only anaerobic growth was observed. Major cellular fatty acids were C_14:0, C_16:0 and C_16:1 ω7c, while major polar lipids were phosphatidylethanolamine and phosphatidylglycerol. The DNA G+C content was 42.2 mol% based on the genomic DNA data. Phylogenetic analyses based on 16S rRNA genes and the housekeeping genes, gapA, pyrH, recA and gyrB, revealed that the strain formed a distinct lineage at species level in the genus Vibrio of the family Vibrionaceae. These results and those from genomic, chemotaxonomic and physiological studies strongly support the assignment of a novel Vibrio species. The name Vibrio salinus sp. nov. is proposed for the novel species, with DNF-1^T (=?BCRC 81209^T?=?JCM 33626^T) as the type strain. This newly proposed species represents the second example of the genus Vibrio that has been demonstrated to be capable of anaerobic growth by fixing N₂ as the sole nitrogen source.

     

Isozymes of isocitrate dehydrogenase from an obligately psychrophilic bacterium, Vibrio sp. strain ABE-1: purification, and modulation of activities by growth conditions

Each of the two isozymes, which are different in thermostability and quaternary structure, of isocitrate dehydrogenase (NADP+) [IDH: EC 1.1.1.42] was purified to an electrophoretically homogeneous state from an obligately psychrophilic marine bacterium, Vibrio sp. strain ABE-1. Hydrophobic chromatography was an efficient procedure to separate the two isozymes from each other. The isoelectric points of isozyme I (IDH-I; a dimer, Mr 88,100) and isozyme II (IDH-II; a monomer, Mr 80,500) were found to be pH 4.9 and 5.2, respectively. The two isozymes were similar in amino acid compositions, though there were slight differences in the contents of nonpolar and hydroxyl amino acids. However, their NH2-terminal amino acid sequences and immunochemical properties were clearly different from each other. The NH2-terminal amino acid sequence analysis also indicated that the subunits of IDH-I are chemically identical or highly homologous. Non-immuno-crossreactivity between the isozymes enabled us to measure the intracellular contents of the isozymes. IDH-I and -II were found to be differentially regulated in vivo by various growth conditions. IDH-I was induced by acetate, while IDH-II remained almost unchanged.     

Ring cleavage and degradative pathway of cyanuric acid in bacteria.

The degradative pathway of cyanuric acid [1,3,5-triazine-2,4,6(1H,3H,5H)-trione] was examined in Pseudomonas sp. strain D. The bacterium grew with cyanuric acid, biuret, urea or NH4+ as sole source of nitrogen, and each substrate was entirely metabolized concomitantly with growth. Enzymes from strain D were separated by chromatography on DEAE-cellulose and three reactions were examined. Cyanuric acid (1 mol) was converted stoichiometrically into 1.0 mol of CO2 and 1.1 mol of biuret, which was conclusively identified. Biuret (1 mol) was converted stoichiometrically into 1.1 mol of NH4+, about 1 mol of CO2 and 1.0 mol of urea, which was conclusively identified. Urea (1 mol) was converted into 1.9 mol of NH4+ and 1.0 mol of CO2. The reactions proceeded under aerobic or anoxic conditions and were presumed to be hydrolytic. Data indicate that the same pathway occurred in another pseudomonad and a strain of Klebsiella pneumoniae.     

Na+-driven ATP synthesis of a psychrophilic marine bacterium, Vibrio sp. strain ABE-1

Abstract: In vivo ATP synthesis of a psychrophilic marine bacterium, Vibrio sp. strain ABE-1, derived from endogenous respiration, was examined. ATP was synthesized at both pH 6.5 and 8.5 after the start of the endogenous respiration by supplying O₂ to the anaerobic cell suspension. The ATP synthesis at pH 6.5, but not at pH 8.5, was completely inhibited by a H⁺ conductor, carbonylcyanide m -chlorophenylhydrazone (CCCP). The CCCP-resistant ATP synthesis at pH 8.5 was strongly inhibited by an inhibitor of the respiration-dependent primary Na⁺ pump, 2- n -heptyl-4-hydroxyquinoline N -oxide, and essentially required Na⁺. These results show that this bacterium synthesizes ATP at pH 6.5 by electrochemical potentials across the membrane Δ ∼ μ _H+, whereas at pH 8.5 by Δ ∼ μ _Na+ but not Δ ∼ μ _H+.     

Siansivirga zeaxanthinifaciens gen. nov., sp. nov., a novel zeaxanthin-producing member of the family Flavobacteriaceae isolated from coastal seawater of Taiwan

A strictly aerobic, Gram-negative, rod-shaped bacterium (strain CC-SAMT-1(T)) showing gliding motility was isolated from coastal seawater of China Sea, Taiwan. Strain CC-SAMT-1(T) synthesizes all-trans-zeaxanthin (6.5 ± 0.5 mg g(-1) dry biomass) as a predominant xanthophyll carotenoid. As determined by 16S rRNA gene analysis, strain CC-SAMT-1(T) shared very high sequence similarity to the members of the genera Mariniflexile (96.1-95.3%) and Gaetbulibacter (96.0-95.9%); however, it formed a distinct phyletic lineage distantly associated with Mariniflexile species. Polar lipid profile constitutes phosphatidylethanolamine, four unidentified aminolipids, four unidentified lipids, and an unidentified glycolipid. Strain CC-SAMT-1(T) contains excessive unidentified aminolipid lipid (AL2-4) and glycolipid contents, and therefore clearly distinct from Mariniflexile species. Major fatty acids (> 5% of total fatty acids) were iso-C(15:0) (14.8%), iso-C(17:0) 3-OH (11.8%), iso-C(15:1) G (10.6%), anteiso-C(15:0) (9.7%), C(16:0) (8.1%), iso-C(16:0) 3-OH (7.9%), iso-C(15:0) 3-OH (7.5%), and summed feature 3 (containing C(16:1) ω6c and/or C(16:1) ω7c) (7.5%). Menaquinone-6 (MK-6) was major respiratory quinone. DNA G+C content was 33.7 mol%. Based on polyphasic taxonomy, strain CC-SAMT-1(T) represents a novel genus and species in the family Flavobacteriaceae for which the name Siansivirga zeaxanthinifaciens gen. nov., sp. nov. is proposed. The type strain is CC-SAMT-1(T) (= BCRC 80315(T) = JCM 17682(T)).