Synthesis of collagenase by the phytopathogenic bacterium Corynebacterium rathayii

The collagenase-producing bacterium tentatively called Empedobacter collagenolyticum was recently identified as Corynebacterium rathayii. Production of collagenase was studied in different media containing peptones or peptides of known sequences. A hexapeptide, Pro-Ala-Gly-Pro-Pro-Gly, is an inducer almost as good as collagen.     

Corynebacterium aquatimens sp. nov., a lipophilic Corynebacterium isolated from blood cultures of a patient with bacteremia

An unknown lipophilic coryneform bacterium isolated from the blood cultures of a patient with bacteremia was characterized by phenotypic and molecular genetic methods. Chemical analysis revealed the presence of short chain mycolic acids consistent with the genus Corynebacterium. The DNA G+C content was 60.8mol%. Comparative 16S rRNA gene sequence analysis demonstrated that the isolate represents a new subline within the genus Corynebacterium. The closely phylogenetic relative of the unknown bacterium was found to be C. tuscaniense (97.8% sequence similarity). Partial rpoB gene sequence revealed that strain IMMIB L-2475(T) exhibited 13.5% sequence divergence with C. tuscaniense. The unknown bacterium was distinguished from C. tuscaniense by, DNA-DNA hybridization, cellular fatty acid profiles, MALDI-TOF analyses of cell extracts and biochemical tests. Based on the phylogenetic and phenotypic criteria, it is proposed that this bacterium be classified as new species, Corynebacterium aquatimens sp. nov., and is represented by strain IMMIB L-2475(T) (=DSM 45632(T)=CCUG 61574(T)).     

Taxonomic studies on Corynebacterium beticola (Abdou)

Morphological, physiological and chemical studies were performed on the type strain of Corynebacterium beticola in an attempt to clarify its taxonomy. The results indicate that Corynebacterium beticola is a Gram negative, facultatively anaerobic bacterium which should be assigned to the genus Erwinia as Erwinia herbicola .     

Identification of the emerging skin pathogen Corynebacterium amycolatum using PCR-amplification of the essential divIVA gene as a target

The actinomycete Corynebacterium amycolatum is a saprophytic bacterium usually associated with the human skin, but it is at present considered an emergent pathogen as it is isolated from nosocomial settings from samples of immunosuppressed patients. The conventional method to distinguish C. amycolatum from closely related species is mainly based on phenotypic or chemotaxonomic studies. We developed a molecular method to identify rapidly C. amycolatum based on the use of different primers for amplification of the cell division divIVA gene using conventional or real-time PCR. This technique was used for the first time to distinguish C. amycolatum from the closely related Corynebacterium striatum, Corynebacterium minutissimum and Corynebacterium xerosis, without the requirement of further molecular analysis. The suitability of the identification method was tested on 51 clinical isolates belonging to the nonlipophilic fermentative group of corynebacteria (cluster C. striatum/C. amycolatum), which were accurately characterized by sequencing a 0.8 kb fragment of the 16S rRNA gene.     

Genome sequence of Corynebacterium nuruki S6-4 T, isolated from alcohol fermentation starter

Corynebacterium nuruki S6-4(T), isolated from Korean alcohol fermentation starter, is a strictly aerobic, nonmotile, Gram-positive, and rod-shaped bacterium belonging to the genus Corynebacterium and the actinomycete group. We report here the draft genome sequence of C. nuruki strain S6-4(T) (3,106,595 bp, with a G+C content of 69.5%).     

Collagenase production by Achromobacter iophagus.

Achromobacter iophagus produced collagenase (EC 3.4.24.3) when cultured aerobically in buffer containing 5% peptone. The bacterium is non-pathogenic and tests on rabbits indicated that the culture medium was atoxic. The collagenase, which hydrolyzed insoluble and soluble native collagen, was purified by (NH4)2 SO4 precipitation, starch block electrophoresis, and gel filtration. It was shown to be serologically distinct from Clostridium histolyticum collagenase and to have molecular weight and sedimentation coefficient values of approx. 112 000 and 5.3 S, respectively.     

A new levan producing bacterium,Corynebacterium laev aniformans nov. spec.

Summary Raw sewage and activated sludge have been shown to be good sources for isolating a levan-synthesising bacterium. The morphological, cultural and physiological characteristics of the bacterium have been described and the designation.Corynebacterium laevaniformans, nov. spec. has been proposed for it. Some of the factors which influence levan synthesis are reported.     

Purification and characterization of a marine bacterial collagenase.

A true collagenase was isolated from the culture fluid of a marine bacterium which has been designated Vibrio B-30 (ATCC 21250). Collagenase production was obtained only in media containing collagen or certain degradation products of collagen. Partial purification on DEAE-cellulose and Sephadex G-200 columns produced active enzyme which was free of nonspecific proteases but which contained two collagenases. The two collagenases have the same apparent molecular size, and evidence is presented to support the theory that one collagenase is derived from the other. Vibrio B-30 collagenase appears to be a tetramer with a molecular weight of about 105 000 composed of two different subunits (mol wt 24 000 and 28 000). Some of the properties of the Vibrio collagenase are compared with those of Clostridium histolyticum collagenase. Molecular weights, subunit structures, specificity and mode of collagen hydrolysis, insensitivity to diisopropyl fluorophosphate and calf serum, and sensitivity to certain metal ion complexing agents and isopropyl alcohol are similar for the collagenases from both organisms. However, Vibrio B-30 collagenase and Clostridium collagenase differ immunologically and electrophoretically.     

Purification and characterization of O-Acetylserine sulfhydrylase of Corynebacterium glutamicum

We highly purified O-acetylserine sulfhydrylase from the glutamate-producing bacterium Corynebacterium glutamicum. The molecular mass of the purified enzyme was 34,500 as determined by SDS-polyacrylamide gel electrophoresis, and 70,800 as determined by gel filtration chromatography. It had an apparent Km of 7.0 mM for O-acetylserine and a Vmax of 435 micromol min-1 (mg x protein)-1. This is the first report of the cysteine biosynthetic enzyme of C. glutamicum in purified form.     

Genome Sequence of the Corynebacterium pseudotuberculosis Cp316 Strain,Isolated from the Abscess of a Californian Horse

The bacterium Corynebacterium pseudotuberculosis is of major veterinary importance because it affects livestock, particularly sheep, goats, and horses, in several countries, including Australia, Brazil, the United States, and Canada, resulting in significant economic losses. In the present study, we describe the complete genome of the Corynebacterium pseudotuberculosis Cp316 strain, biovar equi, isolated from the abscess of a North American horse.     

环化腺苷酸对细菌生长的影响

用大肠杆菌(Escherichia coli AS 1.797)、北京棒状杆菌(Corynebacterium pekinense AS1.299)和巨大芽孢杆菌(Bacills megatertum AS 1.217)研究了细胞内环化腺苷酸(cAMP)浓度和外源cAMP对细胞生长的影响。结果表明,大肠杆菌在不同碳源中生长时,细胞的生长量随细胞内cAMF’浓度升高而降低。在以葡萄糖作碳源时,细胞内cAMP浓度低,外源cAMP。对生长有抑制作用,而cAMP的类似物5'-AMP则无抑制作用。在以乳糖、麦芽糖和甘油分别作碳源时,细胞内cAMP浓度高,外源cAMP对生长无影响。北京捧状杆菌以葡萄糖作碳源时,细胞生长也受外源cAMP的抑制,但cAMP的抑制作用不是专一的,它的作用可用类似物5’-AMP来代替。自身不合cAMP的巨大芽孢杆菌在不同碳原(包括葡萄糖)中生长时,生长不受外源cAMP抑制,也不受5’-Amt’的影响。因此认为,cAMP不是细菌生长的必需物,而是生长调节物,但这种调节物对巨大芽孢杆菌无效。     

A Corynebacterium glutamicum gene conferring multidrug resistance in the heterologous host Escherichia coli.

A chromosomal DNA fragment from the erythromycin-sensitive bacterium Corynebacterium glutamicum ATCC 13032 was shown to mediate resistance against erythromycin, tetracycline, puromycin, and bleomycin in Escherichia coli. Multicopy cloning of the fragment did not cause a resistance phenotype in C. glutamicum. The corresponding gene encodes a hydrophobic protein with 12 potential transmembrane-spanning ex-helical segments showing similarity to drug-H+ antiporters.     

Production and release of surfactant byCorynebacterium lepus in hydrocarbon and glucose media

Summary Corynebacterium lepus produced a considerable amount of extracellular surfactant during growth in a mineral salts medium containing hexadecane as the sole carbon source. The study revealed that the bacterium also produced a large amount of surfactant when grown on glucose, but in this case the surface active agent was cell bound. The surfactant was released from the cells when they were treated with hexadecane after growth. Tetradecane also showed a good capability for release of the surfactant. Decane and octane were less effective than hexadecane and tetradecane.     

Draft Genome Sequence of Corynebacterium bovis DSM 20582, Which Causes Clinical Mastitis in Dairy Cows

Bovine mastitis represents the most economically important disease in dairy cows and can be caused by Corynebacterium bovis, a commensal in the bovine udder. The draft genome sequence provides insights into the adaptation of this bacterium to the bovine habitat and its lipolytic capabilities to utilize components of cow's milk.     

Effects of pure n-alkanes and crude oil on bacterial phospholipid classes and molecular species determined by electrospray ionization mass spectrometry

Phospholipids are major components of bacterial membrane. Furthermore, the growth in vitro on xenobiotics such as n-alkanes, aromatic compounds or alkanols bring about to a bacterial membrane adaptive response. Concerning this work, we studied the membrane lipid composition of a hydrocarbon-degrading gram-positive bacterium (Corynebacterium sp.) on a soluble substrate and we detected four different phospholipid classes: phosphatidylglycerol, phosphatidylinositol, cardiolipin and acyl phosphatidylglycerol. In addition, a study of the lipid composition was performed after an in vitro culture on either pure n-alkane or crude oil. The growths on such hydrophobic substrates showed major qualitative and quantitative modifications. In the case of a growth on either heneicosane or crude oil, an increase of odd-numbered fatty acids was observed. Furthermore, the phospholipid polar head group composition was highly influenced by the crude oil addition. These modifications were, respectively, interpreted as the consequence of hydrocarbon assimilation and membrane fluidity adaptation. Finally, Corynebacterium sp. was taken back on the initial ammonium acetate substrate in order to determine its restoration abilities after a petroleum contamination.     

Serological Investigation of Corynebacterium Pseudotuberculosis Infection in Sheep–Correlation between the Hemolysis Inhibition Test and the ELISA Test

Corynebacterium pseudotuberculosis causes caseous lymphadenitis in sheep and goats. The animals may be infected without showing clinical symptoms. Several serotests have therefore been employed to detect infected animals. Shen et al (1982) performed an enzyme linked immunosorbent assay (ELISA) to detect antibodies against the organism using cell wall antigens. Maki et al (1985) found that the toxin of the bacterium was a better antigen for assessing infection in the ELISA test. They reported that the antitoxin ELISA appeared to be as sensitive as the antihemolysin inhibition test (Zaki 1968).     

Differential Effects of Lithium Chloride on In Vitro Growth of Clavibacter michiganense subsp. nebraskense Depending upon Inoculum Source

The bacterium Clavibacter michiganense subsp. nebraskense (Corynebacterium michiganense subsp. nebraskense) was grown in broth cultures and inoculated into corn plants. The plating efficiency of cells from broth cultures was essentially the same on nutrient broth-yeast extract and the semiselective medium for this bacterium, CNS. However, when cells were isolated from Goss bacterial wilt- and blight-infected corn, very few were recovered on CNS compared with the amount recovered on nutrient broth-yeast extract agar. When lithium chloride was omitted from the CNS, recoveries from infected corn were nearly the same as on nutrient broth-yeast extract agar. No other ingredient of CNS was inhibitory, nor did substitution of other salts for lithium chloride cause equal inhibition. The amount of inhibition was proportional to lithium chloride concentration. The inhibition by lithium chloride occurred with several strains of the bacterium isolated from one corn cultivar and with one of the strains recovered from three different cultivars of infected corn.     

The impact of fluid mechanical stress on <Emphasis Type="Italic">Corynebacterium glutamicum</Emphasis> during continuous cultivation in an agitated bioreactor

The effect of mechanical stresses generated by an extreme agitation intensity or a high aeration rate on growth parameters and cell physiology were studied during continuous cultivation of the Gram-positive bacterium Corynebacterium glutamicum. It is concluded that variations in agitation, aeration rate, or dO₂ concentrations down to about 1% of saturation do not damage the bacterial cells or cause a significant change in physiological response, as measured by flow cytometry, even though the cell size was slightly reduced.     

The cytosolic, cell surface and extracellular proteomes of the biotechnologically important soil bacterium Corynebacterium efficiens YS-314 in comparison to those of Corynebacterium glutamicum ATCC 13032

Reference maps of the cytosolic, cell surface and extracellular proteome fractions of the amino acid-producing soil bacterium Corynebacterium efficiens YS-314 were established. The analysis window covers a pI range from 3 to 7 along with a molecular mass range from 10 to 130 kDa. After second-dimensional separation on SDS-PAGE and Coomassie staining, computational analysis detected 635 protein spots in the cytosolic proteome fraction, whereas 76 and 102 spots were detected in the cell surface and extracellular proteomes, respectively. By means of MALDI-TOF-MS and tryptic peptide mass fingerprinting, 164 cytosolic proteins, 49 proteins of the cell surface and 89 extracellular protein spots were identified, representing in total 177 different proteins. Additionally, reference maps of the three cellular proteome fractions of the close phylogenetic relative Corynebacterium glutamicum ATCC 13032 were generated and used for comparative proteomics. Classification according to the Clusters of Orthologous Groups of proteins scheme and abundance analysis of the identified proteins revealed species-specific differences. The high abundance of molecular chaperones and amino acid biosynthesis enzymes in C. efficiens points to environmental adaptations of this recently discovered amino acid-producing bacterium.     

TetZ, a new tetracycline resistance determinant discovered in gram-positive bacteria, shows high homology to gram-negative regulated efflux systems

The complete nucleotide sequence of the tetracycline resistance plasmid pAG1 from the gram-positive soil bacterium Corynebacterium glutamicum 22243 (formerly Corynebacterium melassecola 22243) was determined. The R-plasmid has a size of 19,751 bp and contains at least 18 complete open reading frames. The resistance determinant of pAG1 revealed homology to gram-negative tetracycline efflux and repressor systems of Tet classes A through J. The highest levels of amino acid sequence similarity were observed to the transmembrane tetracycline efflux protein TetA(A) and to the tetracycline repressor TetR(A) of transposon Tn1721 with 64 and 56% similarity, respectively. This is the first time a repressor-regulated tet gene has been found in gram-positive bacteria. A new class of tetracycline resistance and repressor proteins, termed TetA(Z) and TetR(Z), is proposed.