Biomedical subjects

Werner Lubitz

Publications and source records attributed to Werner Lubitz.

At least 37 records · Page 2Linked to original sources

PubMed2004

Antigen discovery and delivery of subunit vaccines by nonliving bacterial ghost vectors.

The bacterial ghost (BG) platform system is a novel vaccine delivery system endowed with intrinsic adjuvant properties. BGs are nonliving Gram-negative bacterial cell envelopes which are devoid of their cytoplasmic contents, yet maintain their cellular morphology and antigenic structures, including bioadhesive properties. The main advantages of BGs as carriers of subunit vaccines include their ability to stimulate a high immune response and to target the carrier itself to primary antigen-presenting cells. The intrinsic adjuvant properties of BGs enhance the immune response to target antigens, including T-cell activation and mucosal immunity. Since native and foreign antigens can be carried in the envelope complex of BGs, combination vaccines with multiple antigens of diverse origin can be presented to the immune system simultaneously. Beside the capacity of BGs to function as carriers of protein antigens, they also have a high loading capacity for DNA. Thus, loading BGs with recombinant DNA takes advantage of the excellent bioavailability for DNA-based vaccines and the high expression rates of the DNA-encoded antigens in target cell types such as macrophages and dendritic cells. There are many spaces within BGs including the inner and outer membranes, the periplasmic space and the internal lumen which can carry antigens, DNA or mediators of the immune response. All can be used for subunit antigen to design new vaccine candidates with particle presentation technology. In addition, the fact that BGs can also carry piggyback large-size foreign antigen particles, increases the technologic usefulness of BGs as combination vaccines against viral and bacterial pathogens. Furthermore, the BG antigen carriers can be stored as freeze-dried preparations at room temperature for extended periods without loss of efficacy. The potency, safety and relatively low production cost of BGs offer a significant technical advantage over currently utilized vaccine technologies.

Adjuvants, Immunologic↗

PubMed2003

Evaluation of the protective efficacy of Vibrio cholerae ghost (VCG) candidate vaccines in rabbits.

An effective Vibrio cholerae vaccine is needed to reduce the morbidity and mortality caused by this pathogen. Despite the availability of current oral vaccines with measurable efficacy, there is need for more effective vaccines with broad-spectrum efficacy in target populations. Recent studies have shown that bacterial ghosts, produced by the expression of cloned lysis gene E, possess adjuvant properties and are immunogenic. In this study, ghosts were prepared from V. cholerae O1 or O139 and evaluated as vaccines in the reversible intestinal tie adult rabbit diarrhea (RITARD) model. Rabbits were orally immunized with different doses of V. cholerae ghost (VCG) formulations. The vaccine formulations elicited high levels of serum vibriocidal titers against indicator strains. The magnitude of the response was measured as the geometric mean titer (GMT) increase for all rabbits in relation to prevaccination titers. The induction of cross protection was evidenced by the ability of serum from VCG-immunized rabbits to mediate complement-dependent killing of both the homologous and the heterologous strains. Immunized rabbits were protected against intraduodenal challenge 30 days after primary immunization. Protective immunity against challenge appeared to be dose dependent and was associated with marked inhibition of colonization. These results indicate that VCGs represent a novel approach to cholera vaccine development and constitute an effective vaccine delivery vehicle.

Animals↗

PubMed2003

Construction of recombinant S-layer proteins (rSbsA) and their expression in bacterial ghosts--a delivery system for the nontypeable Haemophilus influenzae antigen Omp26.

This study has investigated the feasibility of a combination of recombinant surface layer (S-layer) proteins and empty bacterial cell envelopes (ghosts) to deliver candidate antigens for a vaccine against nontypeable Haemophilus influenzae (NTHi) infections. The S-layer gene sbsA from Bacillus stearothermophilus PV72 was used for the construction of fusion proteins. Fusion of maltose binding protein (MBP) to the N-terminus of SbsA allowed expression of the S-layer in the periplasm of Escherichia coli. The outer membrane protein (Omp) 26 of NTHi was inserted into the N-terminal and C-terminal regions of SbsA. The presence of the fused antigen Omp26 was demonstrated by Western blot experiments using anti-Omp26 antisera. Electron microscopy showed that the recombinant SbsA maintained the ability to self-assemble into sheet-like and cylindrical structures. Recombinant E. coli cell envelopes (ghosts) were produced by the expression of SbsA/Omp26 fusion proteins prior to gene E-mediated lysis. Intraperitoneal immunization with these recombinant bacterial ghosts induced an Omp26-specific antibody response in BALB/c mice. These results demonstrate that the NTHi antigen, Omp26, was expressed in the S-layer self-assembly product and this construct was immunogenic for Omp26 when administered to mice in bacterial cell envelopes.

Animals↗

PubMed2003

Recombinant Vibrio cholerae ghosts as a delivery vehicle for vaccinating against Chlamydia trachomatis.

An efficacious vaccine is needed to control the morbidity and burden of rising healthcare costs associated with genital Chlamydia trachomatis infection. Despite considerable efforts, the development of reliable chlamydial vaccines using conventional strategies has proven to be elusive. The 40kDa major outer membrane protein (MOMP) of C. trachomatis is so far the most promising candidate for a subunit vaccine. The lack of satisfactory protective immunity with MOMP-based vaccine regimens to date would suggest that either MOMP alone is inadequate as a vaccine candidate or better delivery systems are needed to optimize the effect of MOMP. Recombinant Vibrio cholerae ghosts (rVCG) are attractive for use as non-living vaccines because they possess strong adjuvant properties and are excellent vehicles for delivery of antigens of vaccine relevance to mucosal sites. The suitability of the ghost technology for designing an anti-chlamydial vaccine was evaluated by constructing a rVCG vector-based candidate vaccine expressing MOMP (rVCG-MOMP) and assessing vaccine efficacy in a murine model of C. trachomatis genital infection. Intramuscular delivery of the rVCG-MOMP vaccine induced elevated local genital mucosal as well as systemic Th1 responses. In addition, immune T cells from immunized mice could transfer partial protection against a C. trachomatis genital challenge to nai;ve mice. These results suggest that rVCG expressing chlamydial proteins may constitute a suitable subunit vaccine for inducing an efficient mucosal T cell response that protects against C. trachomatis infection. Altogether, the potency and relatively low production cost of rVCG offer a significant technical advantage as a chlamydial vaccine.

Animals↗

PubMed2003

Application of broad-range 16S rRNA PCR amplification and DGGE fingerprinting for detection of tick-infecting bacteria.

Ticks play an important role in the transmission of arthropod-borne diseases of viral, protozoal and bacterial origin. The present article describes a molecular-biological based method, which facilitated the broad-range analyses of bacterial communities in ixodid ticks (Ixodes ricinus). DNA was extracted both from single ticks and pooled adult ticks. Eubacterial 16S rRNA gene fragments (16S rDNA) were amplified by polymerase chain reaction (PCR) with broad-range ribosomal primers. Sequences spanning the hypervariable V3 region of the 16S rDNA and representing individual bacterial taxons were separated by denaturing gradient gel electrophoresis (DGGE). For phylogenetic identification, DGGE bands were exised, cloned and sequenced. In addition, we set up a 16S rDNA clone library which was screened by DGGE. Sequences were compared with sequences of known bacteria listed in the GenBank database. A number of bacteria were affiliated with the genera Rickettsia, Bartonella, and Borrelia, which are known to be pathogenic and transmitted by ticks. Two sequences were related to the yet to be cultivated Haemobartonella. To our knowledge, Haemobartonella has never been directly detected in I. ricinus. In addition, members of the genera Staphylococcus, Rhodococcus, Pseudomonas, and Moraxella were detected, which have not been identified in ticks so far. Two bacteria were most closely related to a rickettsial endosymbiont of an Acanthamoeba sp., and to an endosymbiont (Legionellaceae, Coxiella group) of the microarthropod Folsomia candida. The results prove that 16S rDNA genotyping in combination with DGGE analysis is a promising approach for the detection and identification of bacteria infecting ticks, regardless of whether these bacteria are fastidious, obligate intracellular or noncultivable.

Animals↗

PubMed2003

Monitoring the colonization of monuments by bacteria: cultivation versus molecular methods.

Building materials commonly used in wall paintings and monuments (mortar, limestone and sandstone) were inoculated with an artificial consortium composed of 14 microorganisms and incubated for 6 months at 28 degrees C. The colonization of the different materials by the consortium was investigated. Culture-independent techniques revealed the presence of a diversity of bacteria, whereas culture-dependent techniques yielded mainly spore-forming bacteria. The data suggest that plating leads to an overestimation of the number of spore-forming bacteria with respect to quiescent vegetative forms; the latter are less easily cultured, but are readily detected by culture-independent techniques.

Architecture↗

PubMed2003

Sealed bacterial ghosts--novel targeting vehicles for advanced drug delivery of water-soluble substances.

The purpose of the present study was to develop a drug delivery model for water soluble drug substances using the bacterial ghost platform technology. Bacterial ghosts are non-denatured bacterial cell envelopes that are produced by the plasmid encoded gene E mediated lysis. We present a novel method to fill and seal bacterial ghosts for the application as a drug delivery system for fluid, non-anchored substances. E. coli ghosts were filled with the reporter substance calcein and sealed by fusion with membrane vesicles. By flow cytometry and fluorescence microscopy it was shown that bacterial ghosts can be filled with calcein, and that the bacterial ghosts can be sealed by restoring the membranes integrity. The adherence and uptake studies showed that almost all murine macrophages and a lower proportion of human colorectal adenocarcinoma cells took up fluorescence labeled bacterial ghosts. Moreover, these cells also took up effectively sealed E. coli ghosts filled with calcein, which then was released within the cells. Therefore, we propose bacterial ghosts as alternative drug delivery and release vehicles for advanced cell targeting.

Animals↗

PubMed2003

Bacillus barbaricus sp. nov., isolated from an experimental wall painting.

In a project concerning bacterial colonization of experimental wall paintings, a large number of isolates have been acquired with high similarities in their whole-cell protein patterns obtained after SDS-PAGE. Of this group, four strains, designated V2-BIII-A2(T), V2-BI-A9, V2-BI-04 and V2-BII-A8, were chosen for further characterization. Banding patterns obtained after ERIC-PCR were barely distinguishable among these four strains, indicating their affiliation within a single species. The isolates also displayed nearly identical biochemical and physiological features. The chemotaxonomic characteristics, including polar lipids, quinone systems, cell-wall diamino acid composition and fatty acid profiles, were in good agreement with those of numerous previously described Bacillus species. 16S rDNA analysis of strain V2-BIII-A2(T) showed that this bacterium belongs to the genus Bacillus, with highest sequence similarities to Bacillus megaterium (94.6%), Bacillus flexus (94.4%) and the alkaliphilic Bacillus cohnii (94.2%). Based on almost identical biochemical, physiological and chemotaxonomic traits, ERIC-PCR-generated genomic fingerprints and comparative 16S rDNA sequence analysis, it is demonstrated that the four isolates represent a novel species of the genus Bacillus, for which the name Bacillus barbaricus sp. nov. is proposed. The type strain is V2-BIII-A2(T) (= CCM 4982(T) = DSM 14730(T)).

Austria↗

PubMed2003

Aurantimonas coralicida gen. nov., sp. nov., the causative agent of white plague type II on Caribbean scleractinian corals.

A bacterium previously isolated from a diseased colony of the scleractinian coral Dichocoenia stokesi (common name elliptical star coral) was subjected to a detailed polyphasic taxonomic characterization. The isolate, designated WP1T, was halophilic and strictly aerobic and formed golden-orange-pigmented colonies after prolonged incubation. Cells of WP1T were gram-negative, rod-shaped and showed a characteristic branching rod morphology. Chemotaxonomically, WP1T was characterized by having Q-10 as the major respiratory lipoquinone and sym-homospermidine as the main component of the cellular polyamine content. The predominant constituent in the cellular fatty acid profile was C18:1 omega7c, along with C19:0 cyclo omega8c and C16:0. Other fatty acids present in smaller amounts were C17:0, C18:0, C16:1 omega7c, C20:1 omega7c and C18:1 2-OH. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. Minor amounts of diphosphatidylglycerol, phosphatidylmonomethylethanolamine and phosphatidyldimethylethanolamine were present. The G + C content of the genomic DNA was 66.3 mol%. Phylogenetic analysis of the 16S rRNA gene sequence showed that WP1T represents a separate subline of descent within the order 'Rhizobiales' of the 'Alphaproteobacteria'. The new line of descent falls within the group of families that includes the Rhizobiaceae, Bartonellaceae, Brucellaceae and 'Phyllobacteriaceae', with no particular relative within this group. The 16S rRNA gene sequence similarity to all established taxa within this group was not higher than 92.0% (to Mesorhizobium mediterraneum). To accommodate this emerging coral pathogen, the creation of a new genus and species is proposed, Aurantimonas coralicida gen. nov., sp. nov. (type strain WP1T = CIP 107386T = DSM 14790T).

Alphaproteobacteria↗

PubMed2003

Promicromonospora vindobonensis sp. nov. and Promicromonospora aerolata sp. nov., isolated from the air in the medieval 'Virgilkapelle' in Vienna.

Two airborne bacterial isolates designated V45(T) and V54A(T) were characterized in order to determine their taxonomic position. 16S rDNA sequence analysis showed that the two isolates shared 98.1 % sequence similarity. Highest sequence similarities (98.0-98.5 %) were found to Promicromonospora citrea DSM 43110(T) and Promicromonospora sukumoe IFO 14650(T). Detection of a quinone system with the predominant compound MK-9(H(4)), a polar lipid pattern containing phosphatidylglycerol, a fatty acid profile with the predominant acids C(15 : 0) iso and C(15 : 0) anteiso and the diagnostic cell-wall diamino acid L-lysine supported the assignment of the novel isolates to the genus PROMICROMONOSPORA: The two isolates could be distinguished from P. sukumoe by the presence of glycine in the peptidoglycan, and the detection of the cell-wall sugar galactose differentiates them from the two established species of the genus PROMICROMONOSPORA: Each of the two isolates displayed a unique biochemical profile. Results from DNA-DNA hybridizations clearly demonstrated that V45(T) and V54A(T) represent separate species. Based on these data, it is proposed that V45(T) (=IFO 16525(T)=CCM 7044(T)) and V54A(T) (=IFO 16526(T) =CCM 7043(T)) be classified as the type strains of two novel Promicromonospora species, for which the names Promicromonospora vindobonensis sp. nov. and Promicromonospora aerolata sp. nov. are proposed.

Actinobacteria↗

PubMed2003

Generation of Helicobacter pylori ghosts by PhiX protein E-mediated inactivation and their evaluation as vaccine candidates.

Bacterial ghosts are empty cell envelopes, which may be generated by the controlled expression of the PhiX174 lysis gene E in gram-negative bacteria to obtain vaccine candidates. We describe here the application of this technology to Helicobacter pylori. The lysis gene cassette was cloned into an Escherichia coli-Helicobacter pylori shuttle vector and introduced into an H. pylori recipient strain by bacterial conjugation. Temperature induction of the lysis gene cassette revealed a quantitative killing of the H. pylori culture without induction of lysis-resistant bacteria. Biochemical and transmission electron microscopic studies identified structurally intact H. pylori. Prophylactic oral vaccination experiments using these H. pylori ghosts in the BALB/c mouse model showed a significant reduction of the bacterial load in the ghost group, as measured by a quantitative bacterial reisolation procedure. Ten of 10 and 5 of 10 mice were protected, respectively, without the use of a mucosal adjuvant. Coadministration of ghosts with cholera toxin as mucosal adjuvant resulted in a complete protection of 10 of 10 and 8 of 8 mice against H. pylori challenge, with three animals showing a sterile immunity.

Animals↗

PubMed2003

Bacterial ghosts as carrier and targeting systems for mucosal antigen delivery.

The application of new strategies to develop effective vaccines is essential in modern medicine. The bacterial ghost system is a novel vaccine delivery system endowed with intrinsic adjuvant properties. Bacterial ghosts are nonliving gram-negative bacterial cell envelopes devoid of cytoplasmic contents while maintaining their cellular morphology and native surface antigenic structures including bioadhesive properties. They are produced by PhiX174 protein E-mediated lysis of gram-negative bacteria. The intrinsic adjuvant properties of bacterial ghost preparations enhance immune responses against envelope-bound antigens, including T-cell activation and mucosal immunity. Since native and foreign antigens can be expressed in the envelope complex of ghosts before E-mediated lysis, multiple antigens of various origin can be presented to the immune system simultaneously. In addition, the extended bacterial ghost system represents a platform technology for specific targeting of DNA-encoded antigens to primary antigen-presenting cells. The potency, safety and relatively low production cost of bacterial ghosts offer a significant technical advantage, especially when used as combination vaccines.

Adjuvants, Immunologic↗

PubMed2002

Bacterial ghosts as vaccine candidates for veterinary applications.

The application of new strategies to develop effective vaccines is essential in modern veterinary medicine. The bacterial ghost system is a novel vaccine delivery system endowed with intrinsic adjuvant properties. Bacterial ghosts are nonliving Gram-negative bacterial cell envelopes devoid of cytoplasmic contents while maintaining their cellular morphology and native surface antigenic structures including bioadhesive properties. They are produced by PhiX174 protein E-mediated lysis of Gram-negative bacteria. The intrinsic adjuvant properties of bacterial ghost preparations enhance immune responses against envelope bound antigens, including T-cell activation and mucosal immunity. Since native and foreign antigens can be expressed in the envelope complex of ghosts before E-mediated lysis, multiple antigens of various origins can be presented to the immune system simultaneously. The advantages of bacterial ghosts include the simplicity of the production method, safety, independence from the cold chain, and versatility as a combination vaccine.

Animals↗

PubMed2002

Altamira cave Paleolithic paintings harbor partly unknown bacterial communities.

Since it has been reported that microorganisms can affect painting pigments, Paleolithic painting microbiology deserves attention. The present study is the first report on the bacterial colonization of the valuable Paleolithic paintings in the famous Altamira cave (Spain). One sample taken from a painting area in the Polychromes Hall was analyzed culture-independently. This was the first time microbiologists were allowed to take sample material directly from Altamira paintings. Identification methods included PCR amplification of 16S rRNA genes (16S rDNA) and community fingerprinting by denaturing gradient gel electrophoresis (DGGE). The applied approach gave insight into a great bacterial taxonomic diversity, and allowed the detection of unexpected and unknown bacteria with potential effects on the conservation of the painting. Regarding the number of 29 visible DGGE bands in the community fingerprint, the numbers of analyzed clones described about 72% of the phylogenetic diversity present in the sample. Thirty-eight percent of the sequences analyzed were phylogenetically most closely related to cultivated bacteria, while the majority (62%) were most closely related to environmental 16S rDNA clones. Bacteria identified in Altamira were related with sequence similarities between 84.8 and 99.4% to members of the cosmopolitan Proteobacteria (52.3%), to members of the Acidobacterium division (23.8%), Cytophaga/Flexibacter/Bacteroides phylum (9.5%), green non-sulfur bacteria (4.8%), Planctomycetales (4.8%) and Actinobacteria (4.8%). The high number of clones most closely related to environmental 16S rDNA clones showed the broad spectrum of unknown and yet to be cultivated bacteria in Altamira cave.

Archaeology↗

PubMed2002

Investigation of an anaerobic microbial community associated with a corneal ulcer by denaturing gradient gel electrophoresis and 16S rDNA sequence analysis.

The bacterial community manifested in a corneal ulcer was investigated with culture-independent techniques. DNA was extracted from the eye swab, 200-bp fragments spanning the hypervariable V3 region of the 16S rRNA gene (16S rDNA) were amplified by broad-range PCR and genetic fingerprinting of the total bacterial community was performed by denaturing gradient gel electrophoresis (DGGE). Additionally, 16S rDNA clone libraries containing 1500-bp fragments were constructed, clones were screened by DGGE and sequenced. Microorganisms were phylogenetically most closely related to the Cytophaga/Flavobacterium/Bacteroides phylum (eight clones), Fusobacteria (four clones), spirochetes (three clones) and to the low G+C Gram-positive bacteria (two clones). Low sequence similarity values less than 93% to sequences of known bacteria indicated that some bacteria belonged to hitherto unknown genera. Bacteria which were detected in the healthy eye of the same patient, were phylogenetically related to the low G+C and high G+C Gram-positive bacteria (two clones) and to the Proteobacteria (one clone). To our knowledge, this is the first time that such a complex and anaerobic bacterial community normally found in subgingival crevices is reported to play a role in corneal ulceration. Previous treatment of the ulcer with several topical antibiotics had shown no effect for six months. The followed culture-independent identification of spirochetes and Gram-negative, anaerobic bacilli facilitated the appropriate treatment with topical penicillin G, which stopped further destruction of the eye. Results demonstrated that 16S rDNA genotyping in combination with DGGE fingerprinting are appropriate molecular methods for the investigation of severe bacterial infections which might not be detected by conventional cultivation.

Anaerobiosis↗

PubMed2002

Phylogenetic 16S rRNA analysis reveals the presence of complex and partly unknown bacterial communities in Tito Bustillo cave, Spain, and on its Palaeolithic paintings.

Tito Bustillo cave (Ribadesella, Spain) contains valuable Palaeolithic paintings, which date back 15 000-20 000 years. Since 1969, the cave has been open to the public. Rock wall surfaces, spelaeothems and soils are covered by apparent biofilms of phototrophic microorganisms, which develop under artificial lighting. In addition, rock surfaces present conspicuous bacterial growth in the form of round colonies of different colours and about 1-2 mm in diameter. Even the famous Paintings Panel shows some evident microbial growth. In the present study, bacterial communities on the paintings and on the rock surfaces near the paintings were analysed by culture-independent techniques, including polymerase chain reaction (PCR) amplification of bacterial 16S rRNA genes (16S rDNA), phylogenetic sequence analyses and genetic community fingerprinting by denaturing gradient gel electrophoresis (DGGE). DGGE fingerprints showed complex bacterial community patterns. Forty-one clones matching DGGE bands of the community fingerprints were sequenced, representing about 39% of DNA fragments in the DGGE patterns. Phylogenetic sequence analyses revealed a high number of phylogenetically novel 16S rDNA sequence types and a high diversity of putatively chemotrophic and heterotrophic bacteria. Sequences were phylogenetically most closely related to the Proteobacteria (20 clones), green non-sulphur bacteria (three clones), Planctomycetales order (one clone), Cytophaga-Flexibacter- Bacteroides division (one clone) and the Actinobacteria (four clones). Furthermore, we report the presence of members of the Acidobacterium division (12 clones) in a karstic hypogean environment. Members of this phylum have not so far been detected in these particular environments.

Bacteria↗

PubMed2002

Emended descriptions of the genus Micrococcus, Micrococcus luteus (Cohn 1872) and Micrococcus lylae (Kloos et al. 1974).

Nine yellow-pigmented, spherical bacterial strains isolated from a medieval wall painting (strain D7), from indoor air (strains 3, 6, 7, 13C2, 38, 83 and 118) and from an activated-sludge plant (strain Ballarat) were classified by a polyphasic approach. Analyses of the 16S rRNA gene sequences of three representatives (strains D7, 118 and Ballarat) indicated that they all belong to the genus Micrococcus. The three isolates shared the highest sequence similarities with Micrococcus luteus DSM 20030T (97.9-98%), Micrococcus antarcticus AS 1.2372T (97.9-98.3%) and Micrococcus lylae DSM 20315T (97.5-97.9%). DNA-DNA reassociation studies clearly demonstrated that all nine isolates belong to the species M. luteus. However, neither their chemotaxonomic features nor their physiological and biochemical properties were consistent with those of M. luteus DSM 20030T. In contrast to M. luteus DSM 20030T, all isolates investigated possessed MK-8(H2) as the major respiratory quinone, and strain Ballarat had an A4alpha peptidoglycan type. On the basis of analyses of their Fourier transform-infrared spectroscopy spectra, isolates D7, 3, 6, 7, 13C2, 38, 83 and 118 could be grouped into a single cluster separate from M. luteus DSM 20030T, strain Ballarat and M. lylae DSM 20315T. In addition, all these isolates could be distinguished from M. luteus DSM 20030T by their ability to assimilate D-maltose, D-trehalose, DL-3-hydroxybutyrate, DL-lactate, pyruvate and L-histidine and to hydrolyse casein. Strains D7, 3, 6, 7, 13C2, 38, 83 and 118 differed from both M. luteus DSM 20030T and strain Ballarat by their ability to assimilate acetate, L-phenylalanine, L-serine and phenylacetate. Furthermore, REP-PCR fingerprinting yielded one common band for these strains, whereas this band was not observed for M. luteus DSM 20030T, strain Ballarat or M. lylae DSM 20315T. On the basis of these data, the species M. luteus can be divided into three biovars that are distinguished by several chemotaxonomic and biochemical traits: biovar I, represented by M. luteus DSM 20030T; biovar II, represented by strains D7 (= DSM 14234 = CCM 4959), 3, 6, 7, 13C2, 38, 83 and 118; and biovar III, represented by strain Ballarat (= DSM 14235 = CCM 4960). On the basis of the results generated in this study, emended descriptions of the genus Micrococcus and the species M. luteus and M. lylae are given.

Air Microbiology↗

PubMed2002

Georgenia muralis gen. nov., sp. nov., a novel actinobacterium isolated from a medieval wall painting.

Two bacterial strains, designated 1A-C(T) and 3A-1, were studied and, using these results and previously published data, taxonomically classified. Cells of the strains exhibited a rod-coccus cycle. The peptidoglycan determined for 1A-C(T) was of type A4alpha with lysine as the diagnostic cell-wall diamino acid and an interpeptide bridge of L-Lys <-- L-Glu. The menaquinone systems of the two strains contained MK-8(H4) (82-94%) and MK-7(H4) (3-11%). The polar lipid profiles consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol mannoside, two unidentified phospholipids and an unidentified glycolipid. The fatty acid profiles contained predominantly ai-C15:0 and significant amounts of i-C14:0 and i-C15:1 fatty acids. Genomic fingerprints clearly distinguished strains 1A-C(T) and 3A-1 from each other. DNA-DNA relatedness between the two strains (92%) demonstrated that they are members of a single species. Analyses of the 16S rDNA sequences of strains IA-C(T) and 3A-1, which were almost identical (99.6% sequence similarity), and comparison with corresponding sequences demonstrated that they represent a novel lineage within the suborder Micrococcineae, most closely related to species of the genera Beutenbergia, Bogoriella and Cellulomonas (94.7-95.7% sequence similarity). The results demonstrate that the two strains are members of a single new genus and a single novel species. Thus, the name Georgenia muralis gen. nov., sp. nov. is proposed. The type strain is strain 1A-C(T) (= DSM 14418T = CCM 4963T). Another strain of the species is strain 3A-1 (= DSM 14419 = CCM 4964).

Actinomycetales↗