Sequence polymorphisms in ribosomal RNA genes and variations in chromosomal loci of Oenothera odorata and O. laciniata

Numerous studies on Oenothera species have been investigated for the physiological and ecological characteristics. However, no such an information based on molecular cytogenetic has yet been introduced, in turn, is very essential for identifying sequence polymorphisms of rRNA genes with their loci on mitotic phases for further biological researches. In this study, sequence variations of rRNA genes in Oenothera odorata and O. laciniata were examined to identify informative factors as unique or repeat sequences in intra- and inter-specific variations. Intra-specific variation revealed that the sequences of the rRNA genes including the spacer regions were highly conserved revealing only a few variations. From the inter-specific variation, spacer regions of species were completely different as (1) non-homologous sequences in NTS and (2) different type repeat sequences in ITS 1, 2 and 5.8S rRNA, whereas the remaining coding regions were highly conserved. FISH was carried out on mitotic phases using the 5S rDNA of the analyzed sequences. From the interphase and metaphase chromosomes of the examined species, two loci of 5S rDNA in O. odorata and four loci in O. laciniata were confirmed on the telomeric region of the short arm. Due to the small size and unclear centromere of the chromosomes, karyotype could not be completed. However, we confirmed that the chromosomes are organized by meta- and acrocentric chromosomes and the chromosomes with identified loci were assumed to be paired by the location of loci at the telomeric region on the short arm with relative lengths.     

Immunohistochemical localization of Bis protein in the rat central nervous system

We studied the distribution of Bis (Bcl-2 interacting death suppressor) protein in the adult rat brain and spinal cord using immunohistochemistry. Immunoreactivity was observed in specific neuronal populations in distinct nuclei. The most intensely labeled cells were associated with the motor system, including most cranial nerve motor nuclei, Purkinje cells of the cerebellum, the red nucleus, and the ventral motor neurons of the spinal cord. Bis protein was also expressed in several structures associated with the ventricular system, including the subventricular zone of the lateral ventricle and its rostral extension, in the subcommissural organ, and in tanycytes, radial glial cells in the hypothalamus. Using double-labeling techniques, Bis-immunoreactive cells in the rostral migratory stream, coexpressing Bcl-2, were confirmed as glial fibrillary acidic protein-positive astrocytes comprising the glial tubes. The widespread distribution of Bis suggests that this protein has broader functions in the adult rat central nervous system than previously thought, and that it could be associated with a particular role in the rostral migratory system.J.-H. Lee and M.-Y. Lee contributed equally to this study. This work was supported by the KOSEF through the Cell Death Disease Research Center of MRC at the Catholic University of Korea (R13-2002-005-01001-0) and the Catholic Medical Center Research Foundation grant made in the program year of 2002     

Robust regression-based analysis of drug-nucleic acid binding

Outlier detection can be very important in analyzing data from Scatchard plots. In this study, a robust (outlier-resistant) regression procedure was used in conjunction with a Scatchard plot to study the binding of the methylphenazinium cation with double-stranded DNA. The procedures, their results, and their advantages are discussed.     

Engineering tolerance and accumulation of lead and cadmium in transgenic plants

We have studied the utility of the yeast protein YCF1, which detoxifies cadmium by transporting it into vacuoles, for the remediation of lead and cadmium contamination. We found that the yeast YCF1-deletion mutant DTY167 was hypersensitive to Pb(II) as compared with wild-type yeast. DTY167 cells overexpressing YCF1 were more resistant to Pb(II) and Cd(II) than were wild-type cells, and accumulated more lead and cadmium. Analysis of transgenic Arabidopsis thaliana plants overexpressing YCF1 showed that YCF1 is functionally active and that the plants have enhanced tolerance of Pb(II) and Cd(II) and accumulated greater amounts of these metals. These results suggest that transgenic plants expressing YCF1 may be useful for phytoremediation of lead and cadmium.     

A complete sequence of the pGA1611 binary vector

We report the nucleotide sequence of the binary vector pGA1611, which is used for the transformation of foreign DNA into rice. This vector is 13,476 bp long. The 5577- bp T- DNA region consists of a 1987- bp ubiquitine promoter region, 45 bp for the multiple cloning site, a 253- bpnos terminator region, and the 2045- bpCaMV35S- hph- T7 chimaeric gene. The vector backbone (7004 bp) carriesoriT,traJ,trfA,tetA,tetR, andoriV. An 892- bp RB region and the 489- bp LB region are also present The T- DNA possesses 15 unique sites, six of which are at the multiple cloning site. This information will be valuable for cloning foreign DNA and modifying the vector.     

Industrial attributes of β-glucanase produced by Bacillus sp. CSB55 and its potential application as bio-industrial catalyst

Bioprocess and Biosystems Engineering - The β-glucanase produced from Bacillus sp. CSB55 not only depicts the potent industrial characteristics but also relates as bio-industrial catalyst...     

Statistical optimisation of growth conditions and diesel degradation by the Antarctic bacterium,Rhodococcus sp. strain AQ5‒07

Petroleum pollution is a major concern in Antarctica due to the persistent nature of its hydrocarbon components coupled with the region’s extreme environmental conditions, which means that bioremediation approaches are largely inapplicable at present. The current study assessed the ability of the psychrotolerant phenol-degrader, Rhodococcus sp. strain AQ5-07, to assimilate diesel fuel as the sole carbon source. Factors expected to influence the efficiency of diesel degradation, including the initial hydrocarbon concentration, nitrogen source concentration and type, temperature, pH and salinity were studied. Strain AQ5-07 displayed optimal cell growth and biodegradation activity at 1% v/v initial diesel concentration, 1 g/L NH₄Cl concentration, pH 7 and 1% NaCl during one-factor-at-a-time (OFAT) analyses. Strain AQ5-07 was psychrotolerant based on its optimum growth temperature being near 20 °C. In conventionally optimised media, strain AQ5-07 showed total petroleum hydrocarbons (TPH) mineralisation of 75.83%. However, the optimised condition for TPH mineralisation predicted through statistical response surface methodology (RSM) enhanced the reduction to 90.39% within a 2 days incubation. Our preliminary data support strain AQ5-07 being a potential candidate for real-field soil bioremediation by specifically adopting sludge-phase bioreactor system in chronically cold environments such as Antarctica. The study also confirmed the utility of RSM in medium optimisation.

     

Comparative analysis of the secretory proteome of human adipose stromal vascular fraction cells during adipogenesis

Adipogenesis is a complex process that is accompanied by a number of molecular events. In this study, a proteomic approach was adopted to identify secretory factors associated with adipogenesis. A label‐free shotgun proteomic strategy was implemented to analyze proteins secreted by human adipose stromal vascular fraction cells and differentiated adipocytes. A total of 474 proteins were finally identified and classified according to quantitative changes and statistical significances. Briefly, 177 proteins were significantly upregulated during adipogenesis (Class I), whereas 60 proteins were significantly downregulated (Class II). Changes in the expressions of several proteins were confirmed by quantitative RT‐PCR and immunoblotting. One obvious finding based on proteomic data was that the amounts of several extracellular modulators of Wnt and transforming growth factor‐β (TGF‐β) signaling changed during adipogenesis. The expressions of secreted frizzled‐related proteins, dickkopf‐related proteins, and latent TGF‐β‐binding proteins were found to be altered during adipogenesis, which suggests that they participate in the fine regulation of Wnt and TGF‐β signaling. This study provides useful tools and important clues regarding the roles of secretory factors during adipogenic differentiation, and provides information related to obesity and obesity‐related metabolic diseases.     

A newly synthesized,potent tyrosinase inhibitor: 5-(6-Hydroxy-2-naphthyl)-1,2,3-benzenetriol

In searching for new agents with a depigmenting effect, we synthesized a derivative of resveratrol, 5-(6-hydroxy-2-naphthyl)-1,2,3-benzenetriol (5HNB) with a potent tyrosinase inhibitory activity. 5HNB inhibited mushroom tyrosinase with an IC₅₀ value of 2.95 μM, which is more potent than the well-known anti-tyrosinase activity of kojic acid (IC₅₀ = 38.24). The results of the enzymatic inhibition kinetics by Lineweaver–Burk analysis indicated 5HNB inhibits tyrosinase non-competitively when l-tyrosine was used as the substrate. Based on the strong inhibitory action of 5HNB, it is expected that 5HNB can suppress melanin production in which tyrosinase plays the essential role. Our expectation was confirmed by the experimentations with B16 melanoma cells in which 5HNB inhibited melanin production. We propose that 5HNB might have skin-whitening effects as well as therapeutic potential for treating skin pigmentation disorders.     

Novel 1H-pyrrolo[2,3-c]pyridines as acid pump antagonists (APAs)

A series of 1H-pyrrolo[2,3-c]pyridines as acid pump antagonists (APAs) was synthesized and the inhibitory activities against H⁺/K⁺ ATPase isolated from hog gastric mucosa were determined. After elaborating on substituents at N1, C5, and C7 position of 1H-pyrrolo[2,3-c]pyridine scaffold, we have observed that compounds 14f and 14g are potent APAs with H⁺/K⁺ ATPase IC₅₀ = 28 and 29 nM, respectively.