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An eight-year-old boy presented with a fever, abdominal pain, and vomiting. Imaging studies revealed a 10-cm cystic lesion in his right retroperitoneal area with no blood flow and with a pedunculated nodule inside the cavity. He required surgery to remove the lesion, when severe adhesion of the lesion to duodenum and a small vessel-like connection between the lesion and inferior vena cava were dissected to remove the lesion. A histopathological examination revealed that the wall of the main lesion and the vessel-like connection were composed of smooth muscle, elastic and collagen fiber, and stained positive with CD31, which led to the diagnosis of venous malformation. The pedunculated nodule was a fibrin clot with calcification. His postoperative course was uneventful.

Spontaneously developing pocks (S pocks) of Streptomyces azureusATCC14921 were formed by the both functions of conjugative plasmid pSA1 and lysogenic phage SAt2. The formation was affected by the dose of UV irradiation. The mean pock diameter in cultures treated with UV light at 0, 7.1, 14.2 and 21.3×102μW·erg/cm, respectively, were 1.3, 0.4, 2.2, and 0.5 mm. The dose affected conjugative plasmid pSA1 related to pock formation. There was UV damage of autonomous pSA1 replicon and UV induction of the chromosomal integrated sequence. Increases and decreases in the amount of autonomous pSA1 replicon corresponded to increases and decreases, respectively, in the diameter of the pocks. Both pSA1 and SAt2 syntheses were developed in the large pocks (1.3 and 2.2 mm), but only SAt2 synthesis was developed in the pinhole pocks (0.4 and 0.5 mm).

When the latter half of the hup gene encoding a histone-like protein HSl of Streptomyces lividans TK24 was replaced by the kanamycin resistance gene, the hup mutant EY1 grew slowly in liquid medium and this delay was overcome by introduction of the complete hup . EY1 sporulated normally on solid medium, with no serious defects as observed in hupAB mutants of Escherichia coli . Therefore, HSl probably has a role in growth in the presence of liquid medium and this organism may possess another histone-like protein with functions overlapping those of HSl. We cloned the hup2 gene encoding another histone-like protein HSl2, which has two motifs of prokaryotic histone-like protein and eukaryotic histone H1. The amount of HSl2 increased in EY1, determined by western blotting analysis using an anti-His-tagged HSl2 polyclonal antibody. We are entertaining the notion that the increased amount of HSl2 partially suppressed the defects caused by the hup mutation.

Enterococcus sp. K-4, with a bacteriocin-like activity against E. faecium, was isolated from grass silage in Thailand. Morphological, physiological, and phylogenetic studies clearly identified strain K-4 as a strain of E. faecalis. Strain K-4 produced a maximal amount of bacteriocin at 43-45°C. We purified, for the first time, the bacteriocin produced at high temperature by E. faecalis to homogeneity, using adsorption on cells of the producer strain and reversed-phase liquid chromatography. The bacteriocin, designated enterocin SE-K4, is a peptide of about 5 kDa as measured by SDS-PAGE, and Mass spectrometry analysis found the molecular mass of 5356.2, which is in good agreement. The amino acid sequencing of the N-terminal end of enterocin SE-K4 showed apparent sequence similarity to class IIa bacteriocins. Enterocin SE-K4 was active against E. faecium, E. faecalis, Bacillus subtilis, Clostridium beijerinckii, and Listeria monocytogenes. Enterocin SE-K4 is very heat stable.

We isolated BalA1, a representative transformant of thiostrepton‐producing strain Streptomyces azureusATCC14921, which carries an approximately 2.5‐kb chromosomal DNA fragment on a high‐copy‐number plasmid. While strain BalA1 formed little aerial hyphae, its morphological defect was restored by cultivation with S. azureus, S. laurentii, etc. Strain BalA1 strongly inhibited the growth of Bacillus subtilismore than its parent strain, and also inhibited the development of its parent and some Streptomycesstrains with thiostrepton resistance. Furthermore, it induced Streptomyces coelicolorA3(2) to produce undecylprodigiosin, at an early stage of growth. The 2.5‐kb fragment contained two orfs, orf1and truncated orf2. The deduced products were somewhat similar to phosphoserine phosphatase‐like protein and the N‐terminal region of MinD‐like protein, respectively. The individual function of orf1or the function of both orf1and truncated orf2seems to induce particular phenotypes or properties in strain BalA1.

Phage contamination has resulted in abnormal fermentation in silage. We isolated a phage-resistant strain, Lactobacillus plantarumNGRI0101 from silage. The strain carried two plasmids, pLKL (6.8 kb) and pLKS (2.0 kb). By curing and retransformation of the plasmids, we clarified that pLKS has phage resistant activity, characterized as no adsorption inhibition. pLKS has 2,025 bp and three orfs, orf123, orf132, and orf918. The predicted amino acid sequence of the orf918product showed high similarity to those of Rep proteins of Pediococcus halophilusplasmid pUCL287 and Lactobacillus acidophilusplasmid pLA103. The replication origin (ori) was upstream from orf918. There was no gene similar to typical phage resistant genes encoded by known plasmids. The phage resistance of L. plantarumNGRI0101 may possibly be due to a plasmid-encoded abortive infection.

pSA1.1 is a 9.1‐kb multicopy plasmid originally isolated from Streptomyces cyaneus(formerly S. azureus) ATCC 14921. This plasmid accumulates single‐stranded DNA in S. lividansand is therefore considered to replicate by a rolling‐circle replication. In the present work, the repgene encoding the replication initiator protein and the replication origin oriof pSA1.1 were determined. The repand oriare located on separate regions. The Rep protein of pSA1.1 belongs to superfamily I which includes A proteins of phages. Nucleotide sequence of the surrounding putative nicking site of pSA1.1 shows good agreement with those of the pC194 group plasmids and phages. The direction of replication was also determined.

Plasmid pSLL of Streptomyces laurentiiATCC31255 (wild-type strain P0) is a 93-kilobase linear DNA plasmid that carries a protein bound to each 5′ end of the DNA. It was self-transmitted to the pSLL-cured strain by conjugation in solid culture. The pSLL-cured strain carried a circular plasmid, pSLS, and showed a marked decrease in spore formation and thiostrepton productivity, owing to the pSLS. However, by retransmission of pSLL, these things reverted to levels seen in strain PO. Thus, plasmid pSLL suppressed the injurious effects of pSLS on the host mycelia.

The histopathological sequence of hepatorenal lesions in rats after cessation of the repeated administration of CCl4(0.5 ml/kg, po, twice a week for 12 weeks) was examined. In the liver, cirrhotic lesions reduced rapidly after cessation of the CCl4-administration and collagen bundles surrounding the pseudolobules almost disappeared 12 weeks later. In contrast, in the kidney, vacuolation of epithelial cells in the proximal tubules disappeared rapidly but glomerular lesions progressed even after cessation of the CCl4-administration, and marked glomerulosclerosis developed 12 weeks later. Electron microscopically, marked expansion of the mesangial region due to increases of mesangial cells and matrix material, irregular thickening of the capillary basement membrane with mesangial interposition, and various degenerative changes in podocytes including deposition of small-sized droplets were observed.

Numerous rod-shaped bacterial cells were present in amorphous silica which had formed on the copper plate placed in geothermal hot water, under conditions of pH 7.2 and 85±2°C. Bulk genomic DNA in the siliceous deposit was extracted, using lysozymes and the freeze-thaw method. The volume of siliceous deposit formed on one copper plate and the amount of genomic DNA extracted from siliceous deposits exponentially increased with the time of incubation. The phylogenetic diversity in these DNA extracts was investigated by cloning and sequencing of partial 16S rRNA genes obtained by PCR. The bacterial community was composed mainly of three phylogenetic types in domain Bacteria. Cluster I (8 clones) was affiliated with the Aquificales and cluster II (15 clones) was closely related to the genus Thermus. Cluster III (2 clones), the sequences of which were homologous with Gram-positive anaerobic thermophilic bacteria, was also detected. These extremely thermophilic bacteria may possibly contribute to the rapid aggregation of amorphous silica.

The nucleotide sequence of spoIIIE-like and the sporulation-inhibitory and transfer gene (spi) in a conjugative plasmid, pSA1.1, of Streptomyces azureuswere examined to detect the promoter region. Using Southern blotting and a spifragment as probe, spi-like genes were detected in chromosomes of the host and other actinomycetes. These results suggest that there is a spi- and spoIIIE-like gene in chromosomes of some actinomycetes.

Numerous rod‐shaped bacterial cells were present in amorphous silica which had formed on the copper plate placed in geothermal hot water, under conditions of pH 7.2 and 85±2°C. Bulk genomic DNA in the siliceous deposit was extracted, using lysozymes and the freeze‐thaw method. The volume of siliceous deposit formed on one copper plate and the amount of genomic DNA extracted from siliceous deposits exponentially increased with the time of incubation. The phylogenetic diversity in these DNA extracts was investigated by cloning and sequencing of partial 16S rRNA genes obtained by PCR. The bacterial community was composed mainly of three phylogenetic types in domain Bacteria. Cluster I (8 clones) was affiliated with the Aquificales and cluster II (15 clones) was closely related to the genus Thermus. Cluster III (2 clones), the sequences of which were homologous with Gram‐positive anaerobic thermophilic bacteria, was also detected. These extremely thermophilic bacteria may possibly contribute to the rapid aggregation of amorphous silica.

Summary The γ-glutamyltranspeptidase (γ-GTP) gene of Bacillus subtilis (natto) plasmid designated pUH1, which is responsible for polyglutamate production, has been cloned and the nucleotide sequence determined. The sequence contains a single open-reading frame stretching for 1260 bp with a relative molecular mass of 49356. Putative -35 and -10 sequences, TTCAAA and TATTAT, were observed as the consensus sequence for the promoter recognized by the σ43 RNA polymerase of B. subtilis, and the ribosome binding site, the sequence of which was AACGAG, was complementary to the binding sequence of B. subtilis 16S rRNA except for one base. The amino acid sequence of the gene with the segment of putative protein C403 of staphylococcal plasmid pE194 indicates homology, whereas that with Escherichia coli and mammalian γ-GTPs does not show any similarity at all.

Syrian hamsters of the APA strain (APA hamsters) develop spontaneous mesangial thickening in the renal glomeruli from an early age. They also develop focal and segmental glomerulosclerosis (FSG) at and after 6 months of age. In this study, histopathological, immunohistochemical and lectin histochemical examinations were conducted to clarify the modification of the spontaneous renal lesions of APA hamsters by streptozotocin(SZ)‐induced diabetes. Histopathological analysis revealed that the expansion of the mesangial region was more prominent and the thickening of the glomerular basement membrane (GBM) was weaker in SZ‐treated animals than in non‐treated ones. Immunohistochemical analysis suggested that type IV collagen and laminin were involved in the expansion of the mesangial region and thickening of the GBM. In lectin histochemical analysis, podocytes, capillary endothelial cells, GBM and a part of mesangial region of SZ‐treated animals were positive for RCA120and GSL‐I with neuraminidase‐pretreatment although they were negative for these lectins in non‐treated animals. These results suggest that the spontaneous glomerular lesion of APA hamsters is modified qualitatively and quantitatively by SZ‐induced diabetes.

When exponentially growing cells of Clostridium saccharoperbutylacetonicum(ATCC 13564) were exposed to hypertonic concentrations of sucrose (0.3–0.5 M), rapid degradation of the cell wall occurred (sucrose‐induced autolysis). The morphological changes from the original rod‐shaped cells to protoplasts during the sucrose‐induced autolysis were investigated by phase contrast and electron microscopy. When the cells were autolysed in the sucrose solution (0.35 M), each cell began to swell at the middle or at one pole and then formed a small bulb at the swollen part. The bulb consisted of the cytoplasm which was enveloped by the plasma membrane and extruded from the small gap produced by the degradation of the cell wall. The bulb gradually enlarged as lysis progressed, and finally became a protoplast which had no cell wall. The large pre‐division cell frequently formed the bulb at the middle (septal site), while the small post‐division cell formed the bulb at the pole.

Sporulation-stimulating compounds were screened by using mutant PK100a of Streptomyces azureus ATCC 14921, in which spore formation was markedly inhibited by the pock-forming plasmid pSA1.1. On agar media, cysteine, bacitracin, glutathione and ß-NAD induced the formation of coloured spores or spore mass of strain PK100a. These compounds also stimulated the spore formation of the wild-type and its plasmid-cured (good spore-forming) strains and the growth of aerial mycelia of these three strains. This screening method appears to be an effective method for the screening of substances that stimulate spore formation and mycelial growth of streptomycetes or that overcome the inhibitory effect of pock-forming plasmids.

The bio-deposition of amorphous silica, which occurred in vitroby exposure to the extremely thermophilic bacterium Thermusspp. began from the latter part of the exponential phase of growth of the bacteria. The concentration with which the deposition occurred exceeded the solubility of amorphous silica of neutral pH at the temperature 60~85°C. Our observations suggest that Thermusspp. promotes the formation of siliceous minerals in a geothermal environment.

We isolated BalA1, a representative transformant of thiostrepton-producing strain Streptomyces azureus ATCC14921, which carries an approximately 2.5-kb chromosomal DNA fragment on a high-copy-number plasmid. While strain BalA1 formed little aerial hyphae, its morphological defect was restored by cultivation with S. azureus, S. laurentii, etc. Strain BalA1 strongly inhibited the growth of Bacillus subtilis more than its parent strain, and also inhibited the development of its parent and some Streptomyces strains with thiostrepton resistance. Furthermore, it induced Streptomyces coelicolor A3(2) to produce undecylprodigiosin, at an early stage of growth. The 2.5-kb fragment contained two orfs, orf1 and truncated orf2. The deduced products were somewhat similar to phosphoserine phosphatase-like protein and the N-terminal region of MinD-like protein, respectively. The individual function of orf1 or the function of both orf1 and truncated orf2 seems to induce particular phenotypes or properties in strain BalA1.

pSA1.1 is a 9.1-kb multicopy plasmid originally isolated from Streptomyces cyaneus (formerly S. azureus) ATCC 14921. This plasmid accumulates single-stranded DNA in S. lividans and is therefore considered to replicate by a rolling-circle replication. In the present work, the rep gene encoding the replication initiator protein and the replication origin ori of pSA1.1 were determined. The rep and ori are located on separate regions. The Rep protein of pSA1.1 belongs to superfamily I which includes A proteins of phages. Nucleotide sequence of the surrounding putative nicking site of pSA1.1 shows good agreement with those of the pC194 group plasmids and phages. The direction of replication was also determined.

Streptomyces plasmid pSA1.1 accumulated single-stranded DNA as replication intermediates in S. lividans; therefore, this plasmid was considered to replicate by a rolling-circle mechanism. A DNA-binding protein (pI > 9.7 and about 10 kDa) was purified on a denatured DNA-Cellulose column, then on a native DNA-Cellulose column. The N-terminal amino acid sequence of this protein has a high homology with bacterial histone-like proteins. In the gel retardation assay, this protein bound with the single-stranded DNA of pSA1.1. We propose that this protein may participate in the replication of pSA1.1.