Leclercia adecarboxylata Gen. Nov., Comb. Nov., formerly known asEscherichia adecarboxylata.

The nameLeclercia adecarboxylata is proposed for a group of the family Enterobacteriacae previously known asEscherichia adecarboxylata. Leclercia adecarboxylata can be phenotypically differentiated from all other species of Enterobacteriaceae. The members of this species are positive for motility, indole production, methyl red, growth in the presence of KCN, malonate, beta-galactosidase, beta-xylosidase, esculin hydrolysis, gas production fromd-glucose, and acid production fromd-cellobiose,d-lactose, melibiose,l-rhamnose, adonitol,d-arabitol, dulcitol, and salicin; the strains were negative for Voges-Proskauer, citrate (Simmons), H₂S (Kligler), lysine and ornithine decarboxylases, arginine dihydrolase, phenylalanine deaminase, gelatinase, DNase, Tween-80 hydrolysis, and acid production from myoinositol and alpha-methyl-d-glucoside. Fermentation ofd-raffinose,d-sucrose, andd-sorbitol is variable with strains. DNA relatedness of 11 strains ofL. adecarboxylata to three strains including the type strain of this species averaged 80% in reactions at 65°C. DNA relatedness to other species in Enterobacteriaceae was 2%–32%, indicating that this species was placed in a new genusLeclercia gen. nov. The type strain ofL. adecarboxylata is ATCC 23216.     

d-Pentose metabolism byBacteroides vulgatus strain 8482

Bacteroides vulgatus strain 8482 metabolizedd-arabinose by a mechanism involving a 32 (top to bottom) cleavage of the arabinose carbon skeleton. During growth in the presence of 1-¹⁴C-d-arabinose, acetate, propionate, and succinate were labeled, but during growth in the presence of 5-labeledd-arabinose, only labeled acetate and succinate were formed. The metabolism ofd-ribose by strain 8482 differed from that ford-arabinose. Strain 8482 converted glycolic acid and glycine to acetate and succinate, but not propionate, by a mechanism involving cleavage of the glycine and glycolic acid carbon skeletons and equilibration of carbons 1 and 2 of glycolic acid and glycine with nonequivalent metabolic pools. The metabolism ofd-arabinose,d-ribose,d-glycine, andd-glycolic acid by strain 8482 was similar, in some respects, to that ofBacteroides fragilis strain 2044, but differed substantially from the metabolism of the same substances byBacteroides ruminicola strain B₁4.     

Lactose utilization byVibrio vulnificus

The ability of wild-type strains ofVibrio vulnificus to utilize lactose as a sole source of carbon and energy and produce acid in lactose-containing media is associated with the appearance of spontaneous lactose-utilizing mutants. These contain increased activities of an enzyme able to hydrolyzeo-nitrophenyl--d-galactoside as well as lactose. This activity is constitutive in some mutants and inducible by both lactose and isopropyl--d-thiogalactoside in others. A limited survey of otherVibrio species indicates thatV. pelagius also can acquire, by mutation, the ability to grow on and make acid from lactose. No immunological cross-reaction was detected between the enzymes fromVibrio and the -galactosidases ofEscherichia coli andKlebsiella.     

Enterobacter cowaniisp. nov., a New Species of the Family Enterobacteriaceae

The name Enterobacter cowanii sp. nov. is proposed for a group of organisms referred to as NIH Group 42. Members of this species are Gram-negative, motile rods conforming to the definition of the family Enterobacteriaceae. The DNA relatedness of nine strains of NIH Group 42 to the proposed type strain of this species averaged 85% at 70°C, whereas the relatedness to other species within the family Enterobacteriaceae was less than 38%. Because the DNA relatedness (5–38%) is closer to species of the genus Enterobacter than to other species of the family, the members of NIH Group 42 were placed in the genus Enterobacter. The majority of strains of E. cowanii were isolated from clinical specimens. A culture of the type strain (888-76) has been deposited in the Japan Collection of Microorganisms as JCM 10956. Received: 22 June 2000 / Accepted: 26 June 2000     

Stereoselective formation of a 2′(3′)-aminoacyl ester of a nucleotide

Summary Reaction ofDl-serine and adenosine-5-phosphorimidazolide in the presence of adenosine-5-(O-methylphosphate) and imidazole resulted in the stereoselective synthesis of the aminoacyl nucleotide ester 2(3)-O-seryl-adenosine-5-(O-methylphosphate). The enantiomeric excess ofd-serine incorporated into 2(3)-O-seryl-adenosine-5-(O-methylphosphate) was about 9%. Adenylyl-(5N)-serine and an unknown product also incorporated an excess ofd-serine; however, serylserine showed an excess ofl-serine. The relationship of these results to the origin of the biological pairing ofl-amino acids and nucleotides containingd-ribose is discussed.     

Enterobacter kobei sp. nov., a new species of the family Enterobacteriaceae resembling Enterobacter cloacae

The name Enterobacter kobei sp. nov. is proposed for a group of organisms referred to as NIH Group 21 at the National Institute of Health, Tokyo. The members of this species are Gram-negative, motile rods conforming to the definition of the family Enterobacteriaceae. The DNA relatedness of 23 strains of NIH Group 21 to the representative proposed as the type strain of this species averaged 82% at 70°C, whereas the relatedness to other species within the family Enterobacteriaceae was less than 42%. Because the phenotypic resemblance to Enterobacter cloacae is very close and the DNA relatedness (12–42%) is closer to species of the genus Enterobacter than to other species of the family, the members of NIH Group 21 were placed in the genus Enterobacter. Close phenotypic and genetic relationships were also found between NIH Group 21 and a member of a group of organisms referred to as Enteric Group 69 at the Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, USA. It is suggested that the latter could be regarded as a subspecific rank of E. kobei, though this is subject to study of further strains. The majority of strains of E. kobei were isolated from clinical specimens. A culture of the type strain (NIH 1485-79) has been deposited in the Japan Collection of Microorganisms as JCM 8580. Received: 22 March 1996 / Accepted: 19 April 1996     

Deoxyribonucleic acid relatedness inYersinia enterocolitica andYersinia enterocolitica-like organisms

Yersinia enterocolitica andY. enterocolitica-like strains were characterized by DNA relatedness. These strains formed four distinct DNA relatedness groups: (i) the 5 classical biotypes ofY. enterocolitica sensu stricto as designated by Wauters; (ii) strains that are rhamnose positive and also positive in tests for melibiose, α-methyl-d-glucoside, raffinose, and Simmons' citrate; (iii) strains that are rhamnose positive but negative in tests for melibiose, α-methyl-d-glucoside, and raffinose; (iv) sucrose-negative, Voges-Proskauer-negative, trehalose-positive strains.     

Enzymatic conversion of D-galactose to D-tagatose: heterologous expression and characterisation of a thermostable L-arabinose isomerase from Thermoanaerobacter mathranii

The ability to convert d-galactose into d-tagatose was compared among a number of bacterial l-arabinose isomerases (araA). One of the most efficient enzymes, from the anaerobic thermophilic bacterium Thermoanaerobacter mathranii, was produced heterologously in Escherichia coli and characterised. Amino acid sequence comparisons indicated that this enzyme is only distantly related to the group of previously known araA sequences in which the sequence similarity is evident. The substrate specificity and the Michaelis–Menten constants of the enzyme determined with l-arabinose, d-galactose and d-fucose also indicated that this enzyme is an unusual, versatile l-arabinose isomerase which is able to isomerise structurally related sugars. The enzyme was immobilised and used for production of d-tagatose at 65 °C. Starting from a 30% solution of d-galactose, the yield of d-tagatose was 42% and no sugars other than d-tagatose and d-galactose were detected. Direct conversion of lactose to d-tagatose in a single reactor was demonstrated using a thermostable -galactosidase together with the thermostable l-arabinose isomerase. The two enzymes were also successfully combined with a commercially available glucose isomerase for conversion of lactose into a sweetening mixture comprising lactose, glucose, galactose, fructose and tagatose.     

Edwardsiella hoshinae,a new species of enterobacteriaceae

Eight strains isolated from birds, reptiles, and water constitute a new DNA hybridization group that is 37–58% related toEdwardsiella tarda and less than 10% related to other species of Enterobacteriaceae (SI nuclease method). This homogeneous group (78–100% relatedness within the group) constitutes a new species that is namedEdwardsiella hoshinae sp. nov. (type strain, CIP 78.56 ATCC 33379). Strains of this species produce acid fromd-mannitol, sucrose,d-trehalose, and salicin, and give a positive malonate test. Seven other strains that produced acid fromd-mannitol and sucrose (but not fromd-trehalose and salicin) and were malonate negative were found to belong to theEdwardsiella tarda DNA hybridization group. The base composition of the DNAs ofE. tarda andE. hoshinae is 55–58 mol% G+C.     

Numerical taxonomy ofKlebsiella pneumoniae strains isolated from clinical and nonclinical sources

A total of 180 clinical and nonclinical isolates ofKlebsiella pneumoniae, for which 99 characteristics were recorded, were subjected to numerical taxonomy analysis. Of these strains, 172 clustered into five major groups, with an overall similarity of 64%. Intragroup similarities ranged from 77 to 82%, with the subgroups corresponding to the speciesK. pneumoniae sensu stricto, K. oxytoca, andKlebsiella spp. 1, 2, and 3. Biochemical tests useful in distinguishing the species included production of indole, degradation of pectate, growth at 10°C, fecal coliform response, production of urease, fermentation of inulin andd-tartrate, utilization ofl-arginine and gentisate andm-hydroxybenzoate, and pigment formation ond-gluconate ferric citrate agar.     

Characterization of motile and acetoin-negative Klebsiella pneumoniae strains by DNA: DNA hybridization

Hybridization studies were carried out to determine the extent of divergence between different members of the Enterobacteriaceae and group D, previously described by numerical analysis of phenotypic characters, and comprising strains isolated from surface waters. This group, apparently belonging in or related to the genus Citrobacter on the basis of the IMViC tests differs from this taxon by numerical analysis and DNA base composition. Our work reveals a DNA relatedness of 81–89% between the centrotype strain of this group and the genus Klebsiella. Although strains of group D show positive motility and negative Voges-Proskauer reactions, a comparison of their phenotypic characters leads us to consider that the strains with a high level of hybridization within this group belong to K. pneumoniae. These results suggest a complete revision of the traditional classification scheme of the genus Klebsiella.With the technical assistance of Nicole Marquis     

Arabinoxylan-degrading enzyme system of the fungusAspergillus awamori: purification and properties of an α-l-arabinofuranosidase

An -l-arabinofuranosidase produced by the fungusAspergillus awamori had molecular mass of approximately 64 kDa on sodium dodecyl sulphate/polyacrylamide gel electrophoresis (SDS-PAGE) and was optimally active at pH 4.6 and 50°C. The enzyme, which chromatographed as a single component on SDS-PAGE, appeared to consist of two iso-enzymes of pI 3.6 and 3.2. Acting in isolation, the -l-arabinofuranosidase had only a very limited capacity to releasel-arabinose (less than 11%) directly from arabinoxylans that had been extracted from a number of plant cell wall preparations using 18% alkali, but a much higher proportion of thel-arabinose (46%) was released from a wheat straw arabinoxylan that had been isolated by steam treatment. There was a marked synergistic effect between the -l-arabinofuranosidase and an endo-(1 4)--d-xylanase produced byA. awamori in both the rate and extent of the release ofl-arabinose from both oat straw and wheat straw arabinoxylans, suggesting thatl-arabinose-substituted oligosaccharides generated by the endoxylanase action were better substrates for enzyme action. A novel property of the -l-arabinofurasidase was its capacity to release a substantial proportion (42%) of feruloyll-arabinose from intact wheat straw arabinoxylan. The concerted action of the -l-arabinofuranosidase and endoxylanase released 71% of the feruloyll-arabinose and 69% of thep-coumaroyll-arabinose substituents from the wheat straw arabinoxylan.     

Pentose metabolism byBacteroides ruminicola subsp.brevis strain B14

The fermentation ofd-arabinose byBacteroides ruminicola strain B₁4 occurs in a manner similar to or identical with that shown previously forl-arabinose metabolism by the organism, a combination of hexose resynthesis and the Embden-Meyerhof sequence. The use ofd-arabinose by strain B₁4 was repressed by prior growth in medium containingd-glucose and induced by prior growth in the presence ofl-arabinose ord-xylose. The use ofd-ribose andd-xylose by strain B₁4 is different from that ford-arabinose. During growth in the presence of 1-14C-d-arabinose, labeled acetate, propionate, and succinate were formed, whereas during 1-14C-d-ribose growth only labeled acetate and propionate were obtained. Under the conditions used,d-xylose growth failed to allow formation of acetate, propionate, or succinate. Strain B₁4 incorporates label from 1- or 2-labeled glycine into acetate, propionate, and succinate by a mechanism involving the cleavage of glycine and equilibration of glycine carbons 1 and 2 with different metabolic pools.     

Acidiphilium aminolytica sp. nov.: An acidophilic chemoorganotrophic bacterium isolated from acidic mineral environment

Acidiphilium aminolytica is proposed for a species of the genusAcidiphilium. Acidiphilium aminolytica can be phenotypically differentiated from all other species of the genusAcidiphilium. The seven strains of this species that have been studied are Gram-negative, aerobic, mesophilic, non-sporeforming, motile, and rod-shaped bacteria. They grow between pH 3.0 and 6.0, but not at pH 6.5. They yield positive results in tests for hippuric acid hydrolysis, catalase and urease production. Oxidase, esculin hydrolysis, and -galactosidase tests are negative. They can used-glucose,d-galactose, inositol, sorbitol,l-lysine,l-glutamate,l-arginine, -alanine,dl-4-aminobutyrate,dl-5-aminovalerate, sperimine, or diaminobutane as a sole carbon source, but cannot use elemental sulfur and ferrous iron as an energy source. The DNA base composition is 58.7–59.2 G+C mol%. The major isoprenoid quinone is ubiquinone with ten isoprene unit (Q-10). The major fatty acid is the C_18:1 fatty acid. Two ornithine amide lipids, the C_18:1 fatty acid esters of -N-3-hydroxystearylornithyltaurine and -N-3-hydroxystearylornithine, are detected as the polar aminolipid. DNA relatedness between this species and the other species ofAcidiphilium, the generaAcidomonas, andAcidobacterium was 29 to 2%. These results indicate, that this new species should be placed in the genusAcidiphilium. The type strain (strain 101) ofA. aminolytica is JCM 8796.     

Production ofd-mannitol fromd-aldopentoses by the yeastRhodotorula minuta

Rhodotorula minuta produced 16% ofd-mannitol and 3% ofd-arabinitol when cultivated ond-ribose, 4% of mannitol and 11% of arabinitol when grown ond-xylose, 5% ofd-mannitol and 5% ofd-arabinitol when grown ond-arabinose, and 5% ofd-mannitol and 6% ofd-arabinitol when cultivated ond-lyxose.     

<Emphasis Type="Italic">Halobacillus locisalis</Emphasis> sp. nov., a halophilic bacterium isolated from a marine solar saltern of the Yellow Sea in Korea

A Gram-positive, motile, endospore-forming and rod-shaped halophilic bacterial strain MSS-155 (KCTC 3788 and KCCM 41687) was isolated from a marine solar saltern of the Yellow Sea in Korea and was subjected to a polyphasic taxonomic study. This organism grew at temperature of 10.0–42.0°C with an optimum of 35°C. Strain MSS-155 grew optimally in the presence of 10% NaCl and did not grow in the absence of NaCl. The cell wall peptidoglycan type of strain MSS-155 was A4 based on l-Orn-d-Asp. Strain MSS-155 was also characterized chemotaxonomically by having menaquinone-7 (MK-7) as the predominant isoprenoid quinone and anteiso-C_15:0 as the major fatty acid. The DNA G+C content was 44.0 mol%. Phylogenetic analysis based on 16S rDNA sequences showed that strain MSS-155 falls within the radiation of the cluster comprising Halobacillus species. Levels of 16S rDNA sequence similarity between strain MSS-155 and the type strains of four Halobacillus species were in the range 97.6–98.8%. Strain MSS-155 exhibited levels of DNA-DNA relatedness of 6.2–11.2% to the type strains of Halobacillus species described previously. On the basis of phenotypic properties, phylogeny, and genomic data, strain MSS-155 should be placed in the genus Halobacillus as a member of a novel species, for which we propose the name Halobacillus locisalis sp. nov.Communicated by W.D. Grant     

Plasmid-mediated nicotine degradation inArthrobacter oxidans

The spontaneous loss byArthrobacter oxidans cells of the nicotine-degrading ability (Nic⁺) was 0.06%. It could be increased by treatment with plasmid-curing agents up to 8%. It was possible by conjugation to restore the Nic⁺ phenotype in such cured derivatives and to transfer the Nic⁺ character to Nic^- Arthrobacter species. Plasmid DNA, 160 kb in size as judged by contour length measurements, could be isolated from cleared lysates ofA. oxidans cells by acridine yellow chromatography. Agarose gel electrophoresis of DNA isolated fromArthrobacter exconjugates revealed the occurrence of plasmid DNA within these strains; its mobility was similar to that of the plasmid DNA present inA. oxidans. Although the expression and inducibility of the transferred genes was poor in most of theArthrobacter species exconjugants, apparently authentic 6-hydroxy-l-nicotine oxidase could be identified in these cells after enrichment by an enzyme-specific chromatography.Abbreviations 6-HDNO 6-hydroxy-d-nicotine oxidase - 6-HLNO 6-hydroxy-l-nicotine oxidase - kb kilobase - Nic⁺ ability to usel- ord-nicotine as sole carbon and nitrogen source - Nic^- absence of Nic⁺ character Enzymes (EC 1.5.3.5.) 6-Hydroxy-l-nicotine oxidase, 6-hydroxy-l-nicotine: oxygen oxidoreductase - (EC 1.5.3.6.) 6-hydroxy-d-nicotine oxidase, 6-hydroxy-d-nicotine: oxygen oxidoreductase - (EC 3.1.4.22) ribonuclease A, ribonucleate 3-pyrimidino-oligo-nucleotidohydrolase     

DNA relatedness among serovars ofListeria monocytogenes sensu lato

Sixty-six strains ofListeria monocytogenes (as defined in the eighth edition ofBergey's Manual of Determinative Bacteriology) were characterized by DNA relatedness. These strains formed five distinct DNA relatedness groups: (i)L. monocytogenes sensu stricto (30 strains) including the type spain ATCC 15313; (ii) serovar 5 strains (9 strains) corresponding to L. bulgarica; (iii) L. inocua (11 strains of serovars 6a, 6b, 4ab, and undesignated ones) including the reference strains; (iv) six strains of serovars 6a and 6b; (v) ten strains of various serovars. These five groups were clearly distinct fromL. grayi (4 strains) andL. murrayi (3 strains).     

Induction of aldose reductase activity inCandida guilliermondii by pentose sugars

Summary Cell extracts ofCandida guilliermondii grown ind-xylose,l-arabinose,d-galactose,d-glucose,d-mannose and glycerol as sole carbon sources possessed NADPH-dependent aldose reductase activity, but no NADH-dependent activity was detected.d-xylose andl-arabinose were the best inducers of aldose reductase activity. The highest enzyme activity ind-xylose orl-arabinose-grown cells was observed first withl-arabinose followed byd-xylose as substrates of the enzymatic reaction. However, only low activity was found ind-glucose,d-mannose andd-galactose-grown cells, indicating that these carbon sources cause catabolite repression. Enzyme activities induced ind-xylose-grown cells were twice as high as those obtained from the cells under resting conditions. Furthermore, the level of induction of aldose reductase activity depended on the initial concentration ofd-xylose. The present study shows that aldose reductase activity may be efficiently induced by pentose sugars of hemicellulosic hydrolysates and weakly by hemicellulosic hexoses.     

d-arabinose metabolism byBacteroides fragilis strain 2044

During growth in the presence of 1-14C-d-arabinose,Bacteroides fragilis strain 2044 formed labeled succinic, acetic, and propionic acis. Degradation of the acids by the Schmidt reaction revealed that at least 89% of the succinate radioactivity was found in the methylene carbons and that 75% and 84% of the label in propionate and acetate were found in the noncarboxyl carbons of these molecules. No label was found in acetate, propionate, or succinate during growth of strain 2044 in the presence of 5-3H-d-arabinose. Strain 2044 converted radioactivity from 1- or 2-labeled glycolic acid and glycine to succinate by a mechanism involving cleavage of the glycine and glycolic acid carbon skeletons. Label from 1- or 2-labeled glycine and 2 but not 1-labeled glycolic acid was found in acetate. Uniformly labeled 14C-glyoxalate gave rise to labeled acetate, but not succinate.Bacteroides fragilis strain 2044 metabolizesd-arabinose by a mechanism involving a 32 cleavage of the molecule.