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At least 19 recordsLinked to original sources

PubMed2005

Phenotypic and genetic characterization of clinical isolates of CDC coryneform group A-3: proposal of a new species of Cellulomonas, Cellulomonas denverensis sp. nov.

CDC coryneform group A-3 bacteria are rare human pathogens. In this study, six group A-3 isolates (two from blood, one from cerebrospinal fluid, and one each from homograft valve, lip wound, and pilonidal cyst) were compared to the type strains of phenotypically related organisms, Cellulomonas fimi, Cellulomonas hominis, Oerskovia turbata, and Sanguibacter suarezii, and characterized by phenotypic, chemotaxonomic, and genotypic studies. DNA-DNA reassociation analysis identified two genomic groups, and phylogenetic analysis of the 16S rRNA gene sequence identified the taxonomic positions of these groups to genus level. Two groups were defined, and both were more closely related to Cellulomonas species: one group of three strains, for which we propose the new species Cellulomonas denverensis sp. nov., with the type strain W6929 (ATCC BAA-788(T) or DSM 15764(T)), was related to C. hominis ATCC 51964(T) (98.5% 16S rRNA gene sequence similarity), and the second group of three strains was related to C. hominis ATCC 51964(T) (99.8 to 99.9% 16S rRNA gene sequence similarity). The definition of this new Cellulomonas species and the confirmation of three strains as C. hominis serve to further clarify the complex taxonomy of CDC coryneform group A-3 bacteria and will assist in our understanding of the epidemiology and clinical significance of these microorganisms.

Actinomycetales Infections↗

PubMed1995

Identification of some clinical strains of CDC coryneform group A-3 and A-4 bacteria as Cellulomonas species and proposal of Cellulomonas hominis sp. nov. for some group A-3 strains.

CDC coryneform group A-3 and A-4 bacteria were defined by Hollis and Weaver in 1981, but their taxonomic position is still unclear. By using biochemical and chemotaxonomical methods, four clinical strains belonging to CDC coryneform groups A-3 (n = 2) and A-4 (n = 2) were studied and could be assigned to the genus Cellulomonas, resulting in the first description of Cellulomonas strains isolated from clinical specimens. CDC coryneform group A-3 and A-4 strains were compared with the type strains of the seven species constituting the genus Cellulomonas at present as well as with the closely related species Oerskovia turbata, Oerskovia xanthineolytica, and Jonesia denitrificans, but their biochemical patterns were not compatible with the patterns of any of those species. Almost the entire sequences of the 16S rRNA genes of one representative strain of both CDC taxa were determined, and comparative sequence analysis confirmed the placement of the CDC coryneform group A-3 and A-4 strains studied in the Cellulomonas-Oerskovia subbranch of the actinomycetes. Both CDC taxa exhibited > 99% base pair homology within their 16S rDNAs. On the basis of phenotypic and molecular data, we formally propose a new species, Cellulomonas hominis sp. nov., for the CDC coryneform group A-3 bacteria examined. The type strain is DSM 9581. The precise taxonomic status of the CDC coryneform group A-4 strains studied remains to be established by quantitative DNA-DNA hybridizations.

Actinomycetales↗

PubMed2000

Cellulomonas persica sp. nov. and Cellulomonas iranensis sp. nov., mesophilic cellulose-degrading bacteria isolated from forest soils.

Two newly described species of mesophilic, cellulose-degrading, aerobic bacteria were isolated from forest humus soils along the southern border of the Caspian Sea. Cellulomonas persica and Cellulomonas iranensis are proposed as new specific epithets based on comparative sequence analyses of 16S rDNA, DNA-DNA hybridization and phenotypic characteristics. Formal species descriptions are provided.

Actinomycetales↗

PubMed2002

Dissimilatory reduction of Cr(VI), Fe(III), and U(VI) by Cellulomonas isolates.

The reduction of Cr(VI), Fe(III), and U(VI) was studied using three recently isolated environmental Cellulomonas sp. (WS01, WS18, and ES5) and a known Cellulomonas strain ( Cellulomonas flavigena ATCC 482) under anaerobic, non-growth conditions. In all cases, these cultures were observed to reduce Cr(VI), Fe(III), and U(VI). In 100 h, with lactate as electron donor, the Cellulomonas isolates (500 mg/l total cell protein) reduced nitrilotriacetic acid chelated Fe(III) [Fe(III)-NTA] from 5 mM to less than 2.2 mM, Cr(VI) from 0.2 mM to less than 0.001 mM, and U(VI) from 0.2 mM to less than 0.12 mM. All Cellulomonas isolates also reduced Cr(VI), Fe(III), and U(VI) in the absence of lactate, while no metal reduction was observed in either the cell-free or heat-killed cell controls. This is the first report of Cellulomonas sp. reducing Fe(III) and U(VI). Further, this is the first report of Cellulomonas spp. coupling the oxidation of lactate, or other unknown electron donors in the absence of lactate, to the reduction of Cr(VI), Fe(III), and U(VI).

Anaerobiosis↗

PubMed2005

Cellulomonas terrae sp. nov., a cellulolytic and xylanolytic bacterium isolated from soil.

A bacterial strain (DB5(T)), with polysaccharide-degrading activities, was isolated from garden soil in Daejeon, Republic of Korea. The cells were Gram-positive, aerobic or facultatively anaerobic, non-motile straight rods. Phylogenetic analysis based on 16S rRNA gene sequences showed that this strain belongs to the genus Cellulomonas and that it is most closely related to Cellulomonas xylanilytica LMG 21723(T) and Cellulomonas humilata ATCC 25174(T) (98.0 and 97.9% similarity, respectively). Chemotaxonomic data also supported the classification of strain DB5(T) in the genus Cellulomonas, i.e. L-ornithine as the cell-wall diamino acid, anteiso-C(15:0) and iso-C(15:0) as the major fatty acids, MK-9(H(4)) as the predominant menaquinone and the presence of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylinositol mannosides in the polar lipid profile. The results of DNA-DNA hybridization in combination with chemotaxonomic and physiological data demonstrated that strain DB5(T) (=KCTC 19081(T)=NBRC 100819(T)) should be classified as the type strain of a novel species within the genus Cellulomonas, for which the name Cellulomonas terrae sp. nov. is proposed.

Bacterial Typing Techniques↗

PubMed1986

Comparison of Two Cellulomonas Strains and Their Interaction with Azospirillum brasilense in Degradation of Wheat Straw and Associated Nitrogen Fixation.

A mutant strain of Cellulomonas sp. CS1-17 was compared with Cellulomonas gelida 2480 as the cellulolytic component of a mixed culture which was responsible for the breakdown of wheat straw to support asymbiotic nitrogen fixation by Azospirillum brasilense Sp7 (ATCC 29145). Cellulomonas sp. strain CSI-17 was more efficient than was C. gelida in cellulose breakdown at lower oxygen concentrations and, in mixed culture with A. brasilense, it supported higher nitrogenase activity (C(2)H(2) reduction) and nitrogen fixation with straw as the carbon source. Based on gravimetric determinations of straw breakdown and total N determinations, the efficiency of nitrogen fixation was 72 and 63 mg of N per g of straw utilized for the mixtures containing Cellulomonas sp. and C. gelida, respectively. Both Cellulomonas spp. and Azospirillum spp. exhibited a wide range of pH tolerance. When introduced into sterilized soil, the Cellulomonas sp.-Azospirillum brasilense association was more effective in nitrogen fixation at a pH of 7.0 than at the native soil pH (5.6). This was also true of the indigenous diazotrophic microflora of this soil. The potential implications of this work to the field situation are discussed.

Journal Article↗

PubMed2005

The curdlan-type exopolysaccharide produced by Cellulomonas flavigena KU forms part of an extracellular glycocalyx involved in cellulose degradation.

The genus Cellulomonas is comprised of a group of Gram-positive, soil bacteria capable of utilizing cellulose as their sole source of carbon and energy. Cellulomonas flavigena KU was originally isolated from leaf litter and subsequently shown to produce large quantities of a curdlan-type (beta-1,3-glucan) exopolysaccharide (EPS) when provided with an excess of glucose or other soluble carbon-source. We report here that curdlan EPS is also produced by Cellulomonas flavigena KU when growing on microcrystalline cellulose in mineral salts-yeast extract media. Microscopic examination of such cultures shows an adherent biofilm matrix composed of cells, curdlan EPS, and numerous surface structures resembling cellulosome complexes. Those Cellulomonas species that produce curdlan EPS are all non-motile and adhere to cellulose as it is broken down into soluble sugars. These observations suggest two very different approaches towards the complex process of cellulose degradation within the genus Cellulomonas.

Bacterial Adhesion↗

PubMed2005

Cellulomonas bogoriensis sp. nov., an alkaliphilic cellulomonad.

An alkaliphilic, slightly halotolerant, chemo-organotrophic, Gram-positive, rod-shaped bacterium, strain 69B4(T), was isolated from the sediment of the littoral zone of Lake Bogoria, Kenya. Phylogenetically, it is a member of the genus Cellulomonas, showing less than 97.5 % sequence similarity to the type strains of other Cellulomonas species. The highest level of similarity, albeit moderate, was found with respect to Cellulomonas cellasea DSM 20118(T). Chemotaxonomic properties confirm the 16S rRNA gene-based generic affiliation, i.e. a DNA G+C content of 71.5 mol%, anteiso-C(15:0) and C(16:0) as the major fatty acids, MK-9(H(4)) as the major isoprenoid quinone, a peptidoglycan containing L-ornithine as the diamino acid and D-aspartic acid in the interpeptide bridge and phosphatidylglycerol as the only identified main polar lipid. The strain is aerobic to facultatively anaerobic, being capable of growth under strictly anaerobic conditions. Optimal growth occurs between pH values 9.0 and 10.0. On the basis of its distinct phylogenetic position and metabolic properties, strain 69B4(T) represents a novel species of the genus Cellulomonas, for which the name Cellulomonas bogoriensis sp. nov. is proposed. The type strain is 69B4(T) (=DSM 16987(T)=CIP 108683(T)).

Bacterial Typing Techniques↗

PubMed2004

Cellulomonas xylanilytica sp. nov., a cellulolytic and xylanolytic bacterium isolated from a decayed elm tree.

A Gram-positive, aerobic, non-motile bacterium was isolated from a decayed elm tree. Phylogenetic analysis based on 16S rDNA sequences revealed 99.0 % similarity to Cellulomonas humilata. Chemotaxonomic data that were determined for this isolate included cell-wall composition, fatty acid profiles and polar lipids; the results supported the placement of strain XIL11(T) in the genus Cellulomonas. The DNA G+C content was 73 mol%. The results of DNA-DNA hybridization with C. humilata ATCC 25174(T), in combination with chemotaxonomic and physiological data, demonstrated that isolate XIL11(T) should be classified as a novel Cellulomonas species. The name Cellulomonas xylanilytica sp. nov. is proposed, with strain XIL11(T) (=LMG 21723(T)=CECT 5729(T)) as the type strain.

Base Composition↗

PubMed1980

Use of a cellulase-derepressed mutant of cellulomonas in the production of a single-cell protein product from cellulose.

A cellulase-derepressed mutant of a Cellulomonas species was used to produce single-cell protein from crystalline cellulose. In preliminary tests, maximum yield of single-cell protein was obtained at 30 degrees C (pH 7.0) with urea as the nitrogen source. A continuous-flow foam flotation procedure was developed for rapid and efficient separation of bacteria from the culture liquid and cellulose residue. A pH of 4.5 was optimum for foam flotation of this organism. In preliminary trials, recovery was 85% of the cells with the flotation procedure. Cellulomonas was 68% true protein and had an essential amino acid profile featuring a high lysine content (6.5% of protein). The Cellulomonas product was evaluated nutritionally with weanling rats. The net protein utilization value for the protein supplemented with methionine was 50.4% Weight gain of rats on the Cellulomonas diet was similar to that of rats fed a casein diet.

Journal Article↗

PubMed1989

Differential Expression of Xylanases and Endoglucanases in the Hybrid Derived from Intergeneric Protoplast Fusion between a Cellulomonas sp. and Bacillus subtilis.

A stable hybrid obtained by protoplast fusion between a Cellulomonas sp. and Bacillus subtilis exhibits an altered pattern of enzyme induction with different cellulosic substrates. Unlike in the Cellulomonas sp., xylanase was induced in the hybrid organism specifically by xylan, and endoglucanase was induced by carboxymethyl cellulose. The amount and specific activity of xylanase produced by the hybrid were more than those produced by the Cellulomonas sp. beta-Glucosidase which is cell bound or intracellular in the Cellulomonas sp. was secreted by the hybrid organism, and relative amounts of extracellular beta-glucosidase were high. Furthermore, this extracellular beta-glucosidase activity was dependent on the nature of the cellulosic substrate. Endoglucanases synthesized in the hybrid differed in their electrophoretic mobilities as compared with the parental enzymes.

Journal Article↗

PubMed1999

Crystal structure of the purine nucleoside phosphorylase (PNP) from Cellulomonas sp. and its implication for the mechanism of trimeric PNPs.

The three-dimensional structure of the trimeric purine nucleoside phosphorylase (PNP) from Cellulomonas sp. has been determined by X-ray crystallography. The binary complex of the enzyme with orthophosphate was crystallized in the orthorhombic space group P212121 with unit cell dimensions a=64.1 A, b=108.9 A, c=119.3 A and an enzymatically active trimer in the asymmetric unit. X-ray data were collected at 4 degrees C using synchrotron radiation (EMBL/DESY, Hamburg). The structure was solved by molecular replacement, with the calf spleen PNP structure as a model, and refined at 2.2 A resolution. The ternary "dead-end" complex of the enzyme with orthophosphate and 8-iodoguanine was obtained by soaking crystals of the binary orthophosphate complex with the very weak substrate 8-iodoguanosine. Data were collected at 100 K with CuKalpha radiation, and the three-dimensional structure refined at 2.4 A resolution. Although the sequence of the Cellulomonas PNP shares only 33 % identity with the calf spleen enzyme, and almost no identity with the hexameric Escherichia coli PNP, all three enzymes have many common structural features, viz. the nine-stranded central beta-sheet, the positions of the active centres, and the geometrical arrangement of the ligands in the active centres. Some similarities of the surrounding helices also prevail. In Cellulomonas PNP, each of the three active centres per trimer is occupied by orthophosphate, and by orthophosphate and base, respectively, and small structural differences between monomers A, B and C are observed. This supports cooperativity between subunits (non-identity of binding sites) rather than existence of more than one binding site per monomer, as previously suggested for binding of phosphate by mammalian PNPs. The phosphate binding site is located between two conserved beta- and gamma-turns and consists of Ser46, Arg103, His105, Gly135 and Ser223, and one or two water molecules. The guanine base is recognized by a zig-zag pattern of possible hydrogen bonds, as follows: guanine N-1...Glu204 O(epsilon1)...guanine NH2...Glu204 O(epsilon2). The exocyclic O6 of the base is bridged via a water molecule to Asn246 N(delta), which accounts for the inhibitory, but lack of substrate, activity of adenosine. An alternative molecular mechanism for catalysis by trimeric PNPs is proposed, in which the key catalytic role is played by Glu204 (Glu201 in the calf and human enzymes), while Asn246 (Asn243 in the mammalian enzymes) supports binding of 6-oxopurines rather than catalysis. This mechanism, in contrast to that previously suggested, is consistent with the excellent substrate properties of N-7 substituted nucleosides, the specificity of trimeric PNPs versus 6-oxopurine nucleosides and the reported kinetic properties of Glu201/Ala and Asn243/Ala point variants of human PNP.

Amino Acid Sequence↗

PubMed1978

[Peptidoglycan type and cell wall polysaccharide composition of Cellulomonas cartalyticum and some coryneform organisms (author's transl)].

Cellulomonas cartalyticum was found to contain a peptidoglycan type different from that of the other species of Cellulomonas. The diamino acid is lysin instead of ornithine and the interpeptide bridge consists of D-Asp-D-Ser. The same peptidoglycan type occurs in Corynebacterium manihot, Brevibacterium liticum and Arthrobacter luteus. These non cellulolytic organisms are most likely not closely related with Cellulomonas cartalyticum, as indicated by the very different G +C content of their DNA, although they formed a narrow cluster including C. cartalyticum when numeric taxonomical methods were applied.

Actinomycetales↗

PubMed1997

Characterization of cloned endoxylanase from Cellulomonas sp. NCIM 2353 expressed in Escherichia coli.

A 22-kDa xylanase encoded by a cloned gene (XCs16)of Cellulomonas was purified to homogeneity with an overall yield of 44%. It is a basic protein with a pI of 8.1 and has a Km and Vmax of 3 mg/ml and 1150 micromoles/mg/min, respectively, for oat spelt xylan at 55 degrees C and pH 5.8. Homologous xylanase from Cellulomonas could be identified with antibodies raised against purified xylanase encoded by XCs16. The enzyme from Cellulomonas also exhibited identical temperature and pH optimum and had a molecular weight of 23 kDa. Modification of tryptophan residue of purified xylanase resulted in the loss of xylanase activity. This loss could be reversed by the addition of substrate, indicating the involvement of tryptophan residue in the catalytic site.

Actinomycetales↗

PubMed2002

Purine nucleoside phosphorylase from Cellulomonas sp.: physicochemical properties and binding of substrates determined by ligand-dependent enhancement of enzyme intrinsic fluorescence, and by protective effects of ligands on thermal inactivation of the enzyme.

Purine nucleoside phosphorylase (PNP) from Cellulomonas sp., homotrimeric in the crystalline state, is also a trimer in solution. Other features of the enzyme are typical for "low molecular mass" PNPs, except for its unusual stability at pH 11. Purine bases, alpha-D-ribose-1-phosphate (R1P) and phosphate enhance the intrinsic fluorescence of Cellulomonas PNP, and hence form binary complexes and induce conformational changes of the protein that alter the microenvironment of tryptophan residue(s). The effect due to guanine (Gua) binding is much higher than those caused by other ligands, suggesting that the enzyme preferentially binds a fluorescent, most probably rare tautomeric anionic form of Gua, further shown by comparison of emission properties of the PNP/Gua complex with that of Gua anion and its N-methyl derivatives. Guanosine (Guo) and inosine (Ino) at 100 microM concentration show little and no effect, respectively, on enzyme intrinsic fluorescence, but their protective effect against thermal inactivation of the enzyme points to their forming weak binary complexes with PNP. Binding of Gua, hypoxanthine (Hx) and R1P to the trimeric enzyme is described by one dissociation constant, K(d)=0.46 microM for Gua, 3.0 microM for Hx, and 60 microM for R1P. The binding stoichiometry for Gua (and probably Hx) is three ligand molecules per enzyme trimer. Effects of phosphate on the enzyme intrinsic fluorescence are due not only to binding, but also to an increase in ionic strength, as shown by titration with KCl. When corrected for effects of ionic strength, titration data with phosphate are most consistent with one dissociation constant, K(d)=270 microM, but existence of a very weak binding site with K(d)>50 mM could not be unequivocally ruled out. Binding of Gua to the PNP/phosphate binary complex is weaker (K(d)=1.7 microM) than to the free enzyme (K(d)=0.46 microM), suggesting that phosphate helps release the purine base in the catalytic process of phosphorolysis. The results indicate that nonlinear kinetic plots of initial velocity, typical for PNPs, including Cellulomonas PNP, are not, as generally assumed, due to cooperative interaction between monomers forming the trimer, but to a more complex kinetic mechanism than hitherto considered.

Actinomycetales↗

PubMed1995

Phylogenetic analysis of the genera Cellulomonas, Promicromonospora, and Jonesia and proposal to exclude the genus Jonesia from the family Cellulomonadaceae.

The 16S rRNA gene sequences of eight Cellulomonas species, two Promicromonospora species, and Jonesia denitrificans were determined, and these sequences were compared with the sequences of about 50 representatives of the Arthrobacter line of descent in the order Actinomycetales. We found that in spite of its current assignment to the family Cellulomonadaceae, J. denitrificans branches outside the radiation of this taxon and cannot be considered a member of it. The two Promicromonospora species do not cluster separately from Cellulomonas species and are more closely related to Cellulomonas species than to each other.

Actinomycetales↗

PubMed2000

Reclassification of Actinomyces humiferus (Gledhill and Casida) as Cellulomonas humilata nom. corrig., comb. nov.

The placement of Actinomyces humiferus within the genus Actinomyces has always been controversial. A humiferus differs from typical members of the genus both phenotypically and in possessing a relatively high DNA G + C content. Comparative 16S rRNA gene sequencing has shown that A. humiferus is related only distantly to other species of the genus Actinomyces and is, in fact, a member of the genus Cellulomonas. On the basis of phylogenetic evidence, it is proposed that A. humiferus be reclassified in the genus Cellulomonas as Cellulomonas humilata nom. corrig., comb. nov.

Actinomyces↗

PubMed2001

Reclassification of Cellulomonas cellulans (Stackebrandt and Keddie 1986) as Cellulosimicrobium cellulans gen. nov., comb. nov.

Phylogenetic analysis of 16S rDNA provides evidence that Cellulomonas cellulans branches outside the phylogenetic confines of the genus Cellulomonas. The distinct phylogenetic and chemotaxonomic status of Cellulomonas cellulans as a phylogenetic neighbour of the genus Promicromonospora, justifies the description of a new genus for which the name Cellulosimicrobium gen. nov. with the type species Cellulosimicrobium cellulans comb. nov. is proposed.

Actinomycetales↗