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Axel Zeeck - One of the best experts on this subject based on the ideXlab platform.
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Novel α‐L‐Rhamnopyranosides from a Single Strain of Streptomyces by Supplement‐Induced Biosynthetic Steps
European Journal of Organic Chemistry, 2002Co-Authors: Stephanie Grond, Ina Papastavrou, Axel ZeeckAbstract:Various acyl and phenyl α-L-rhamnopyranosides were produced by Streptomyces Griseoviridis (strain Tu 3634) in the presence of different supplements. Some of the added aromatic compounds underwent structural transformations prior to rhamnosylation (1, 3, 5, 8, 9). Especially remarkable was the formation of an indole (9) when 3,5-diaminobenzoic acid was added. Other precursors were not accepted by the strain, but did induce or enhance the biosynthesis of aromatic carboxylic acids from the shikimate pathway. These acids were then transformed into the acyl α-L-rhamnopyranosides 10−13. This can be seen as a new strategy of pathway engineering. With derivatives 4 and 14−17 we gained further insight into the substrate specificity of the rhamnosyltransferase, in particular concerning the competition for rhamnosylation between a carboxylic acid and a phenol or aliphatic hydroxyl group. All isolated metabolites were detected by chemical screening and characterized by spectroscopic methods. The biosynthetic abilities of the strain result in a remarkable structural diversity within the family of α-L-rhamnopyranosides. The strain exemplifies the one strain/many compounds (OSMAC) approach. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)
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structural diversity of 1 o acyl α l rhamnopyranosides by precursor directed biosynthesis with Streptomyces Griseoviridis
European Journal of Organic Chemistry, 2000Co-Authors: Stephanie Grond, Ina Papastavrou, Axel ZeeckAbstract:The ability of Streptomyces Griseoviridis (strain Tu 3634) to glycosylate various carboxylic acids with L-rhamnose was investigated by feeding mainly heteroaromatic and aromatic carboxylic acids to growing cultures. The special application of the precursor-directed biosynthesis (PDB) gave rise to a wide variety of acyl α-L-rhamnopyranosides as novel metabolites. The experiments resulted in furanyl, pyrrolyl, thienyl, indolyl, and pyridyl derivatives (1−8), the analogues 9−24 were generated by feeding fluoro-, hydroxy- or aminobenzoic acids or cinnamic acids. All results are discussed with respect to the substrate specificity of the corresponding enzyme system.
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Structural Diversity of 1‐O‐Acyl α‐L‐Rhamnopyranosides by Precursor‐Directed Biosynthesis with Streptomyces Griseoviridis
European Journal of Organic Chemistry, 2000Co-Authors: Stephanie Grond, Ina Papastavrou, Axel ZeeckAbstract:The ability of Streptomyces Griseoviridis (strain Tu 3634) to glycosylate various carboxylic acids with L-rhamnose was investigated by feeding mainly heteroaromatic and aromatic carboxylic acids to growing cultures. The special application of the precursor-directed biosynthesis (PDB) gave rise to a wide variety of acyl α-L-rhamnopyranosides as novel metabolites. The experiments resulted in furanyl, pyrrolyl, thienyl, indolyl, and pyridyl derivatives (1−8), the analogues 9−24 were generated by feeding fluoro-, hydroxy- or aminobenzoic acids or cinnamic acids. All results are discussed with respect to the substrate specificity of the corresponding enzyme system.
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Acyl α‐L‐Rhamnopyranosides, a Novel Family of Secondary Metabolites from Streptomyces sp.: Isolation and Biosynthesis
European Journal of Organic Chemistry, 2000Co-Authors: Stephanie Grond, Susanne Grabley, Ralf Thiericke, Hans-jörg Langer, Petra Henne, Isabel Sattler, Hans Zähner, Axel ZeeckAbstract:In the course of our chemical screening program, the novel acyl α-L-rhamnopyranosides (1-6) were detected as metabolites from five different strains of Streptomycetes. The structures of all these compounds were elucidated by chemical and spectroscopic methods. The biosynthesis of 1 and 3 was established by feeding 13C-labelled acetate, glycerol, and D-glucose to Streptomyces Griseoviridis (strain Tu 3634), and resulted in a complete labelling pattern of the 2,4-dimethyl-3-furanylcarbonyl and benzoyl residues, as well as the rhamnose moiety. These results reveal biosynthetic pathways of general importance and give an insight into the generation of the hexose phosphates, from which deoxysugars are formed. The acyl rhamnosides are members of a novel family of microbial metabolites and are considered as rhamnoconjugates from Streptomycetes.
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New cineromycins and musacins obtained by metabolite pattern analysis of Streptomyces Griseoviridis (FH-S 1832). II. Structure elucidation.
The Journal of antibiotics, 1996Co-Authors: Andrea Schneider, Axel Zeeck, Julia Späth, Sabine Breiding-mack, Susanne Grabley, Ralf ThierickeAbstract:A detailed analysis of the secondary metabolite pattern produced by Streptomyces Griseoviridis (strain FH-S 1832) using a chemical screening method resulted in the detection, isolation and structure elucidation of new 14-membered lactones of the cineromycin B-type [dehydrocineromycin B (5), oxycineromycin B (7), and 2,3-dihydrocineromycin B (8)], as well as new gamma-lactones related to nigrosporalactone and 4,5-dihydroxy-octa-2,6-dienoic acid esters named musacins A to F (10, 13 approximately 15, 17, 18 and 21). The constitution of these metabolites were deduced from spectroscopic data as well as chemical transformations. The configuration of musacin D (10) was determined by derivatization with chiral acids (Helmchen's method).
Stephanie Grond - One of the best experts on this subject based on the ideXlab platform.
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Mixed Acetate‐Glycerol Biosynthesis and Formation of Benzoate Directly from Shikimate in Streptomyces sp.
European Journal of Organic Chemistry, 2004Co-Authors: Luise Hoffmann, Stephanie GrondAbstract:Biosynthetic studies of γ-butyrolactones and 3-furanylcarbonyl α-L-rhamnopyranosides reveal a new mixed biosynthetic pathway which provides different types of secondary metabolites. The new γ-butyrolactone 1 is produced by Streptomyces sp. (strain GT 61150) together with (propenyl-3-furanyl)carbonyl α-L-rhamnopyranoside (2). Their structures were elucidated by chemical and spectroscopic methods. The biosynthesis of 1 and 2 was established by feeding 13C-labelled acetate and glycerol to Streptomyces sp. and resulted in a complete labelling pattern of 1 and 2. Benzoyl α-L-rhamnopyranoside (3) is a rare compound of the rhamnoside family and is produced by Streptomyces Griseoviridis (strain Tu 3634). [1,7-13C2]Shikimic acid was fed to prove the hypothesis that the benzoyl unit is derived directly from shikimate and not from the plant-like pathway with phenylalanine as an intermediate. The results exemplify a novel bacterial benzoate biosynthesis. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
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Novel α‐L‐Rhamnopyranosides from a Single Strain of Streptomyces by Supplement‐Induced Biosynthetic Steps
European Journal of Organic Chemistry, 2002Co-Authors: Stephanie Grond, Ina Papastavrou, Axel ZeeckAbstract:Various acyl and phenyl α-L-rhamnopyranosides were produced by Streptomyces Griseoviridis (strain Tu 3634) in the presence of different supplements. Some of the added aromatic compounds underwent structural transformations prior to rhamnosylation (1, 3, 5, 8, 9). Especially remarkable was the formation of an indole (9) when 3,5-diaminobenzoic acid was added. Other precursors were not accepted by the strain, but did induce or enhance the biosynthesis of aromatic carboxylic acids from the shikimate pathway. These acids were then transformed into the acyl α-L-rhamnopyranosides 10−13. This can be seen as a new strategy of pathway engineering. With derivatives 4 and 14−17 we gained further insight into the substrate specificity of the rhamnosyltransferase, in particular concerning the competition for rhamnosylation between a carboxylic acid and a phenol or aliphatic hydroxyl group. All isolated metabolites were detected by chemical screening and characterized by spectroscopic methods. The biosynthetic abilities of the strain result in a remarkable structural diversity within the family of α-L-rhamnopyranosides. The strain exemplifies the one strain/many compounds (OSMAC) approach. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)
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structural diversity of 1 o acyl α l rhamnopyranosides by precursor directed biosynthesis with Streptomyces Griseoviridis
European Journal of Organic Chemistry, 2000Co-Authors: Stephanie Grond, Ina Papastavrou, Axel ZeeckAbstract:The ability of Streptomyces Griseoviridis (strain Tu 3634) to glycosylate various carboxylic acids with L-rhamnose was investigated by feeding mainly heteroaromatic and aromatic carboxylic acids to growing cultures. The special application of the precursor-directed biosynthesis (PDB) gave rise to a wide variety of acyl α-L-rhamnopyranosides as novel metabolites. The experiments resulted in furanyl, pyrrolyl, thienyl, indolyl, and pyridyl derivatives (1−8), the analogues 9−24 were generated by feeding fluoro-, hydroxy- or aminobenzoic acids or cinnamic acids. All results are discussed with respect to the substrate specificity of the corresponding enzyme system.
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Structural Diversity of 1‐O‐Acyl α‐L‐Rhamnopyranosides by Precursor‐Directed Biosynthesis with Streptomyces Griseoviridis
European Journal of Organic Chemistry, 2000Co-Authors: Stephanie Grond, Ina Papastavrou, Axel ZeeckAbstract:The ability of Streptomyces Griseoviridis (strain Tu 3634) to glycosylate various carboxylic acids with L-rhamnose was investigated by feeding mainly heteroaromatic and aromatic carboxylic acids to growing cultures. The special application of the precursor-directed biosynthesis (PDB) gave rise to a wide variety of acyl α-L-rhamnopyranosides as novel metabolites. The experiments resulted in furanyl, pyrrolyl, thienyl, indolyl, and pyridyl derivatives (1−8), the analogues 9−24 were generated by feeding fluoro-, hydroxy- or aminobenzoic acids or cinnamic acids. All results are discussed with respect to the substrate specificity of the corresponding enzyme system.
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Acyl α‐L‐Rhamnopyranosides, a Novel Family of Secondary Metabolites from Streptomyces sp.: Isolation and Biosynthesis
European Journal of Organic Chemistry, 2000Co-Authors: Stephanie Grond, Susanne Grabley, Ralf Thiericke, Hans-jörg Langer, Petra Henne, Isabel Sattler, Hans Zähner, Axel ZeeckAbstract:In the course of our chemical screening program, the novel acyl α-L-rhamnopyranosides (1-6) were detected as metabolites from five different strains of Streptomycetes. The structures of all these compounds were elucidated by chemical and spectroscopic methods. The biosynthesis of 1 and 3 was established by feeding 13C-labelled acetate, glycerol, and D-glucose to Streptomyces Griseoviridis (strain Tu 3634), and resulted in a complete labelling pattern of the 2,4-dimethyl-3-furanylcarbonyl and benzoyl residues, as well as the rhamnose moiety. These results reveal biosynthetic pathways of general importance and give an insight into the generation of the hexose phosphates, from which deoxysugars are formed. The acyl rhamnosides are members of a novel family of microbial metabolites and are considered as rhamnoconjugates from Streptomycetes.
Anne Mette Madsen - One of the best experts on this subject based on the ideXlab platform.
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Occupational exposure to microorganisms used as biocontrol agents in plant production.
Frontiers in bioscience (Scholar edition), 2011Co-Authors: Anne Mette MadsenAbstract:Exposure to bioaerosols containing fungi and bacteria may cause various deleterious respiratory health effects. Fungi and bacteria are commercially produced and applied to the environment as microbiological pest control agents (MPCAs). Attention has been drawn towards the exposure and health risks due to the use of commercially important MPCAs. As part of a risk evaluation this paper intends to review whether the exposure to MPCAs (Beauveria bassiana, Verticillium lecanii, Trichoderma harzianum, T. viride, T. polysporum, Paecilomyces fumosoroseus, P. lilacinus, Streptomyces Griseoviridis, Bacillus subtilis and Ba. thuringiensis) exceeds background exposure levels. The paper is further aimed to focus on the aerosolization of MPCAs in relation to exposure and human inhalation. From the few studies about exposures it is concluded that both people handling MPCAs in occupational settings and residents of an area where MPCAs have been applied may be exposed to MPCAs. The highest exposures to MPCAs are found for people applying MPCAs. In 2 of 12 environments exposure to applied MPCAs were higher than exposure to the total number of bacteria or fungi.
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Exposure to bioaerosols during the growth season of tomatoes in an organic greenhouse using Supresivit (Trichoderma harzianum) and Mycostop (Streptomyces Griseoviridis).
Applied and environmental microbiology, 2010Co-Authors: Vinni Mona Hansen, Anne Winding, Anne Mette MadsenAbstract:In working environments, especially in confined spaces like greenhouses, elevated concentrations of airborne microorganisms may become a problem for workers' health. Additionally, the use of microbial pest control agents (MPCAs) may increase exposure to microorganisms. The aim of this study was to investigate tomato growers' exposure to naturally occurring bioaerosol components [dust, bacteria, fungi, actinomycetes, (1-->3)-beta-D-glucans, and endotoxin] and MPCAs applied by drip irrigation. Airborne dust was collected with filter samplers and analyzed for microorganisms by plate counts and total counts using a microscope. Analysis of (1-->3)-beta-D-glucan and endotoxin content was performed by kinetic, chromatic Limulus amoebocyte lysate tests. The fungal strain (Trichoderma harzianum) from the biocontrol product Supresivit was identified by PCR analysis. Measurements were performed on the day of drip irrigation and 1 week, 1 month, and 3 months after the irrigation. T. harzianum from Supresivit could be detected only on the day of treatment. Streptomyces Griseoviridis, an applied MPCA, was not detected in the air during this investigation. We found that bioaerosol exposure increases during the growth season and that exposure to fungi, bacteria, and endotoxin can reach levels during the harvest period that may cause respiratory symptoms in growers. The collected data indicate that MPCAs applied by drip irrigation do not become airborne later in the season.
G M Streshinskaya - One of the best experts on this subject based on the ideXlab platform.
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Cell wall teichoic acids from Streptomyces daghestanicus VKM Ac-1722T and Streptomyces murinus INA-00524T
Mikrobiologiia, 2005Co-Authors: G M Streshinskaya, A S Shashkov, Yu. I. Kozlova, I. V. Alferova, Lyudmila I. EvtushenkoAbstract:The structure of cell wall teichoic acids was studied by chemical methods and NMR spectroscopy in the type strains of two actinomycete species of the “Streptomyces Griseoviridis” phenetic cluster: Streptomyces daghestanicus and Streptomyces murinus. S. daghestanicus VKM Ac-1722t contained two polymers having a 1,5-poly(ribitol phosphate) structure. In one of them, the ribitol units had α-rhamnopyranose and 3-O-methyl-α-rhamnopyranose substituents; in the other, each ribitol unit was carrying 2,4-ketal-bound pyruvic acid. Such polymers were earlier found in the cell walls of Streptomyces roseolus and Nocardiopsis albus, respectively; however, their simultaneous presence in the cell wall has never been reported. The cell wall teichoic acid of Streptomyces murinus INA-00524T was a 1,5-poly(glucosylpolyol phosphate), whose repeating unit was [-6)-β-D-glucopyranosyl-(1→2)-glycerol phosphate-(3-P-]. Such a teichoic acid was earlier found in Spirilliplanes yamanashiensis. The 13C NMR spectrum of this polymer is presented for the first time. The results of the present investigation, together with earlier published data, show that the type strains of four species of the “Streptomyces Griseoviridis” phenetic cluster differ in the composition and structure of their teichoic acids; thus, teichoic acids may serve as chemotaxonomic markers of the species.
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Cell wall teichoic acids from Streptomyces daghestanicus VKM Ac-1722^T and Streptomyces murinus INA-00524^T
Microbiology, 2005Co-Authors: G M Streshinskaya, A S Shashkov, Yu. I. Kozlova, I. V. Alferova, L I EvtushenkoAbstract:The structure of cell wall teichoic acids was studied by chemical methods and NMR spectroscopy in the type strains of two actinomycete species of the “Streptomyces Griseoviridis” phenetic cluster: Streptomyces daghestanicus and Streptomyces murinus. S. daghestanicus VKM Ac-1722^t contained two polymers having a 1,5-poly(ribitol phosphate) structure. In one of them, the ribitol units had α-rhamnopyranose and 3- O -methyl-α-rhamnopyranose substituents; in the other, each ribitol unit was carrying 2,4-ketal-bound pyruvic acid. Such polymers were earlier found in the cell walls of Streptomyces roseolus and Nocardiopsis albus , respectively; however, their simultaneous presence in the cell wall has never been reported. The cell wall teichoic acid of Streptomyces murinus INA-00524^T was a 1,5-poly(glucosylpolyol phosphate), whose repeating unit was [-6)-β-D-glucopyranosyl-(1→2)-glycerol phosphate-(3- P -]. Such a teichoic acid was earlier found in Spirilliplanes yamanashiensis . The ^13C NMR spectrum of this polymer is presented for the first time. The results of the present investigation, together with earlier published data, show that the type strains of four species of the “Streptomyces Griseoviridis” phenetic cluster differ in the composition and structure of their teichoic acids; thus, teichoic acids may serve as chemotaxonomic markers of the species.
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structure of anionic carbohydrate containing cell wall polymers in several representatives of the order actinomycetales
Biochemistry, 2000Co-Authors: Yuliya I Kozlova, G M Streshinskaya, A S Shashkov, L I Evtushenko, Ekaterina Yu Gavrish, I B NaumovaAbstract:: A new teichoic acid was identified in the cell walls of Streptomyces Griseoviridis VKM Ac-622T, Streptomyces sp. VKM Ac-2091, and Actinoplanes campanulata VKM Ac-1319T. The polymer is poly(glycosylglycerol phosphate). The repeating units of the polymer, alpha-galactopyranosyl-(1-->3)-2-acetamido-2-deoxy-beta-galactopyran+ ++ osyl-(1-->1)-glycerols, are in phosphodiester linkage at C-3 of glycerol and C-6 of galactose. The structures of cell wall teichoic acids in the strains Streptomyces chryseus VKM Ac-200T and "Streptomyces subflavus" VKM Ac-484 similar in morphology and growth characteristics are also identical: 1,5-poly(ribitol phosphate) substituted at C-4(2) by 2-acetamido-2-deoxy-beta-glucopyranosyl residues and 1,3-poly(glycerol phosphate). The taxonomic aspects of these results are discussed.
A S Shashkov - One of the best experts on this subject based on the ideXlab platform.
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Cell wall teichoic acids from Streptomyces daghestanicus VKM Ac-1722T and Streptomyces murinus INA-00524T
Mikrobiologiia, 2005Co-Authors: G M Streshinskaya, A S Shashkov, Yu. I. Kozlova, I. V. Alferova, Lyudmila I. EvtushenkoAbstract:The structure of cell wall teichoic acids was studied by chemical methods and NMR spectroscopy in the type strains of two actinomycete species of the “Streptomyces Griseoviridis” phenetic cluster: Streptomyces daghestanicus and Streptomyces murinus. S. daghestanicus VKM Ac-1722t contained two polymers having a 1,5-poly(ribitol phosphate) structure. In one of them, the ribitol units had α-rhamnopyranose and 3-O-methyl-α-rhamnopyranose substituents; in the other, each ribitol unit was carrying 2,4-ketal-bound pyruvic acid. Such polymers were earlier found in the cell walls of Streptomyces roseolus and Nocardiopsis albus, respectively; however, their simultaneous presence in the cell wall has never been reported. The cell wall teichoic acid of Streptomyces murinus INA-00524T was a 1,5-poly(glucosylpolyol phosphate), whose repeating unit was [-6)-β-D-glucopyranosyl-(1→2)-glycerol phosphate-(3-P-]. Such a teichoic acid was earlier found in Spirilliplanes yamanashiensis. The 13C NMR spectrum of this polymer is presented for the first time. The results of the present investigation, together with earlier published data, show that the type strains of four species of the “Streptomyces Griseoviridis” phenetic cluster differ in the composition and structure of their teichoic acids; thus, teichoic acids may serve as chemotaxonomic markers of the species.
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Cell wall teichoic acids from Streptomyces daghestanicus VKM Ac-1722^T and Streptomyces murinus INA-00524^T
Microbiology, 2005Co-Authors: G M Streshinskaya, A S Shashkov, Yu. I. Kozlova, I. V. Alferova, L I EvtushenkoAbstract:The structure of cell wall teichoic acids was studied by chemical methods and NMR spectroscopy in the type strains of two actinomycete species of the “Streptomyces Griseoviridis” phenetic cluster: Streptomyces daghestanicus and Streptomyces murinus. S. daghestanicus VKM Ac-1722^t contained two polymers having a 1,5-poly(ribitol phosphate) structure. In one of them, the ribitol units had α-rhamnopyranose and 3- O -methyl-α-rhamnopyranose substituents; in the other, each ribitol unit was carrying 2,4-ketal-bound pyruvic acid. Such polymers were earlier found in the cell walls of Streptomyces roseolus and Nocardiopsis albus , respectively; however, their simultaneous presence in the cell wall has never been reported. The cell wall teichoic acid of Streptomyces murinus INA-00524^T was a 1,5-poly(glucosylpolyol phosphate), whose repeating unit was [-6)-β-D-glucopyranosyl-(1→2)-glycerol phosphate-(3- P -]. Such a teichoic acid was earlier found in Spirilliplanes yamanashiensis . The ^13C NMR spectrum of this polymer is presented for the first time. The results of the present investigation, together with earlier published data, show that the type strains of four species of the “Streptomyces Griseoviridis” phenetic cluster differ in the composition and structure of their teichoic acids; thus, teichoic acids may serve as chemotaxonomic markers of the species.
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structure of anionic carbohydrate containing cell wall polymers in several representatives of the order actinomycetales
Biochemistry, 2000Co-Authors: Yuliya I Kozlova, G M Streshinskaya, A S Shashkov, L I Evtushenko, Ekaterina Yu Gavrish, I B NaumovaAbstract:: A new teichoic acid was identified in the cell walls of Streptomyces Griseoviridis VKM Ac-622T, Streptomyces sp. VKM Ac-2091, and Actinoplanes campanulata VKM Ac-1319T. The polymer is poly(glycosylglycerol phosphate). The repeating units of the polymer, alpha-galactopyranosyl-(1-->3)-2-acetamido-2-deoxy-beta-galactopyran+ ++ osyl-(1-->1)-glycerols, are in phosphodiester linkage at C-3 of glycerol and C-6 of galactose. The structures of cell wall teichoic acids in the strains Streptomyces chryseus VKM Ac-200T and "Streptomyces subflavus" VKM Ac-484 similar in morphology and growth characteristics are also identical: 1,5-poly(ribitol phosphate) substituted at C-4(2) by 2-acetamido-2-deoxy-beta-glucopyranosyl residues and 1,3-poly(glycerol phosphate). The taxonomic aspects of these results are discussed.