• Journal of Microbiology
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• v.37 no.3
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• pp.141-147
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• 1999

Thirteen transcriptionally-fused carbon starvation mutants, derived from Pseudomonas putida ATCC 12633, were analyzed for their survivability and transcriptional induction profiles upon carbon starvation. One of these mutants, MK114, which exhibited the lowest survivability and the highest induction rate, was selected and further examined under different starvation (nitrogen and phosphate) and stress (osmolarity, H2O2, salts, alcohol, and heat) conditions. Under all tested conditions MK114 induced ${\beta}$-galactosidase activity, implying that the interrupted gene (cst114) is a general starvation and stress response gene. The rate of induction ranged from 2.6-fold for phosphate starvation to 3.7-fold for osmotic shock. The mini-Tn5 flanking DNA was cloned from the chromosome of MK114. The cloned DNA fragment exhibited carbon starvation activity, indicating that this fragment contains a carbon starvation-related promoter region. This region was partially sequenced. Possible physiological roles of Cst114 in a carbon sensing mechanism and in other stress responses are also discussed.

• Biotechnology and Bioprocess Engineering:BBE
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• v.3 no.1
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• pp.11-14
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• 1998

A toluene-oxidizing strain of Pseudomanas mendocina KR1 containing toluene-4-mono-oxygenase (TMO) completely degrades TCE with the addition of toluene as a co-substrate in aerobic condition. In order to construct in situ bioremediation system for TCE degradation without any growth-stimulating nutrients or toxic inducer such as toluene, we used the carbon-starvation promoter of Pseudomonas putida MK1 (Kim, Y. et al., J. bacteriol., 1995). Upon entry into the stationary phase due to the deprivation of nutrients, this promoter is strongly induced without further cell growth. The TMO gene cluster (4.5 kb) was spliced downstream of the carbon starvation promoter of Pseudomonas putida MK1, already cloned in pUC19. TMO under the carbon starvation promoter was not expressed in E. coli cells either in stationary phase or exponential phase. For TMO expression in Pseudomonas strains, tmo and carbon starvation promoter region were recloned into a modified broad-host range vector pMMB67HES which was made from pMMB67HE(8.9 kb) by deletion of tac promoter and lacIq (about 1.5 kb). Indigo was produced by TMO under the carbon starvation promoter in a Pseudomonas strain of post-exponential phase on M9 (0.2% glucose and 1mM indole) or LB. 18% of TCE was degraded in 14 hours after entering the stationary phase at the initial concentration of 6.6 ${\mu}$M in liquid phase.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.11
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• pp.1593-1600
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• 2016

This research was conducted to investigate the physiological consequences of undernourished yak. Twelve Maiwa yak ($110.3{\pm}5.85kg$) were randomly divided into two groups (baseline and starvation group). The yak of baseline group were slaughtered at day 0, while the other group of yak were kept in shed without feed but allowed free access to water, salt and free movement for 9 days. Blood samples of the starvation group were collected on day 0, 1, 2, 3, 5, 7, 9 and the starved yak were slaughtered after the final blood sample collection. The liver and muscle glycogen of the starvation group decreased (p<0.01), and the lipid content also decreased while the content of moisture and ash increased (p<0.05) both in Longissimus dorsi and liver compared with the baseline group. The plasma insulin and glucose of the starved yak decreased at first and then kept stable but at a relatively lower level during the following days (p<0.01). On the contrary, the non-esterified fatty acids was increased (p<0.01). Beyond our expectation, the ketone bodies of ${\beta}$-hydroxybutyric acid and acetoacetic acid decreased with prolonged starvation (p<0.01). Furthermore, the mRNA expression of lipogenetic enzyme fatty acid synthase and lipoprotein lipase in subcutaneous adipose tissue of starved yak were down-regulated (p<0.01), whereas the mRNA expression of lipolytic enzyme carnitine palmitoyltransferase-1 and hormone sensitive lipase were up-regulated (p<0.01) after 9 days of starvation. The phosphoenolpyruvate carboxykinase and pyruvate carboxylase, responsible for hepatic gluconeogenesis were up-regulated (p<0.01). It was concluded that yak derive energy by gluconeogenesis promotion and fat storage mobilization during starvation but without ketone body accumulation in the plasma.

• Journal of Microbiology
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• v.43 no.1
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• pp.44-48
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• 2005

In our previous study, the first structural gene (GGTI) encoding ${\gamma}-glutamyl$ transpeptidase was cloned and characterized from the fission yeast Schizosaccharomyces pombe, and its transcription, using the GGTI-lacZ fusion gene, containing the 1,085 bp upstream region from the translational initiation point, was found to be enhanced by sodium nitroprusside and L-buthionine-(S,R)-sulfoximine (BSO). In the present work, regulation of the GGTI gene was further elucidated. Non-fermentable carbon sources, such as acetate and ethanol, markedly enhanced the synthesis of ${beta}-galactosidase$ from the GGTI-lacZ fusion gene. However, its induction by non-fermentable carbon sources appeared to be independent of the presence of the Pap1 protein. Nitrogen starvation also gave rise to induction of GGTI gene expression in a Pap1-independent manner. The three additional fusion plasmids, carrying 754, 421 and 156 bp regions, were constructed. The sequence responsible for the induction by non-fermentable carbon sources and nitrogen starvation was identified to exist within a -421 bp region of the GGTI gene. Taken together, the S. pombe GGTI gene is regulated by non-fermentable carbon sources and nitrogen starvation.

• Journal of Microbiology and Biotechnology
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• v.15 no.3
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• pp.678-682
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• 2005

The promoter region of a carbon starvation gene isolated from Pseudomonas putida was cloned and analyzed for its potential use for in situ bioremediation and bioprocessing. We constructed a recombinant plasmid pMKD101 by cloning the 0.65 kb promoter region of the gene into the promoter proving vector, pMK301, which contains the lacZ for ${\beta}$-galactosidase activity as a reporter gene. pMKD101 was transformed into the wild-type P. putida MK1, resulting in P. putida RPD101, and analyzed for ${\beta}$-galactosidase activity under different culture conditions. When RPD101 was grown on the minimal medium plus $0.1\%$ glucose as a sole carbon source in batch cultures, ${\beta}$-galactosidase activity was found to be 3.2-fold higher during the stationary phase than during the exponential phase. In chemostat cultures, ${\beta}$-galactosidase activity was found to be 3.1-fold higher at the minimal growth rate (dilution rate=$0.05\;h^{-1}$) than at the maximal growth rate (dilution rate=$0.173;h^{-1}$). The results suggest that a carbon starvation promoter can be utilized to maximize the expression of a desired gene under nutrient limitation.

• Proceedings of the Korean Society of Crop Science Conference
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• 2007.04a
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• pp.65-73
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• 2007

The objective of this study is to understand how regulatory mechanisms respond to sugar status for more efficient carbon utilization and source-sink regulation in plants. So, we need to identify and characterize many components of sugar-response pathways for a better understanding of sugar responses. For this end, genes responding change of sugar status were screened using Arabidpsis cDNA arrays, and confirmed thirty-six genes to be regulated by sucrose supply in detached leaves by RNA blot analysis. Eleven of them encoding proteins for amino acid metabolism and carbohydrate metabolism were repressed by sugars. The remaining genes induced by sugar supply were for protein synthesis including ribosomal proteins and elongation factors. Among them, I focused on three hydrolase genes encoding putative $\beta$-galactosidase, $\beta$-xylosidase, and $\beta$-glucosidase that were transcriptionally induced in sugar starvation. Homology search indicated that these enzymes were involved in hydrolysis of cell wall polysaccharides. In addition to my results, recent transcriptome analysis suggested multiple genes for cell wall degradation were induced by sugar starvation. Thus, I hypothesized that enzyme for cell wall degradation were synthesized and secreted to hydrolyze cell wall polysaccharides producing carbon source under sugar-starved conditions. In fact, the enzymatic activities of these three enzymes increased in culture medium of Arabidopsis suspension cells under sugar starvation. The $\beta$-galactosidase encoded by At5g56870 was identified as a secretory protein in culture medium of suspension cells by mass spectrometry analysis. This protein was specifically detected under sugar-starved condition with a specific antibody. Induction of these genes was repressed in suspension cells grown with galactose, xylose and glucose as well as with sucrose. In planta, expression of the genes and protein accumulation were detected when photosynthesis was inhibited. Glycosyl hydrolase activity against galactan also increased during sugar starvation. Further, contents of cell wall polysaccharides especially pectin and hemicellulose were markedly decreased associating with sugar starvation in detached leaves. The amount of monosaccharide in pectin and hemicellulose in detached leaves decreased in response to sugar starvation. These results supported my idea that cell wall has one of function to supply carbon source in addition to determination of cell shape and physical support of plant bodies.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.3
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• pp.67-74
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• 2003

Starvation promoters can be utilized for in situ bioremediation and for the efficient bioprocessing. Previously we have cloned and characterized strong starvation promoters from envrionmentally relevant bacteria, Pseudomonas putida strains (Y. Kim, and A. Matin, J. Bacteriol. 177:1850-1859, 1995). Here we report the construction of the plasmid pYKS101 using one of the starvation promoters from P. putida MK1. The pYKS101 was found to be useful for a novel starvation promoter-driven gene expression system. Under this system, the target reporter gene, lacZ, was stably integrated into the chromosomal DNA of P. putida MK1. ${\beta}$-galactosidase activity was found to be four-fold higher upon carbon starvation than during exponential growth. The resultant recombinant strain is indigenous to the environment contaminated with various toxic materials, hence can be a good candidate for in situ bioremediation.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.3
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• pp.234-240
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• 2010

The effectiveness of adding powdered zeolite and granular activated carbon (GAC) before starvation into biological reactor for recovering its performances was investigated. Two types of carrier addition in Sequencing Batch Reactor (SBR) system for non-saline and saline wastewater were evaluated after starvation periods. During the experiment, settleablity (SVI), floc size, fractal dimension, $COD_{Mn}$, T-N, T-P removal efficiencies and recovery time were monitored. When the wastewater feeding was resumed after starvation period for 5days, the SVI increased at the beginning of resumption and then decreased with time in both types. And the larger the floc size and fractal dimension of floc, the more increased removal efficiency for $COD_{Mn}$, T-N and T-P was also. Its performance recovery was strongly correlated with floc size and fractal dimension of activated sludge. After resuming the wastewater feeding, the SVI, floc size, fractal dimension, $COD_{Mn}$, T-N, T-P removal efficiency of SBR with carrier improved and reached its initial value faster compared to those of SBR without carrier.

• Transactions of the Korean hydrogen and new energy society
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• v.24 no.4
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• pp.311-319
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• 2013

A clear understanding on cell voltage-reversal behavior due to local hydrogen starvation in a stack is of paramount importance to operate the fuel cell vehicle (FCV) stably since it affects significantly the cell performance and durability. In the present study, a novel experimental method to simulate the local cell voltage-reversal behavior caused by local hydrogen starvation, which typically occurs only one or several cells out of several hundred cells in a stack of FCV, has been proposed. Contrary to the conventional method of overall fuel starvation, the present method of local hydrogen starvation caused the local cell voltage-reversal behavior in a stack very well. Degradation of both membrane electrode assembly (i.e., pin-hole formation) and gas diffusion layer due to an excessive exothermic heat under voltage-reversal condition was also observed clearly.

• Journal of Microbiology and Biotechnology
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• v.26 no.8
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• pp.1464-1472
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• 2016

The BLi03719 protein of Bacillus licheniformis DSM13 belongs to the most abundant extracellular proteins under phosphate starvation conditions. In this study, the function of this phosphate starvation inducible protein was determined. An amino-acid sequence analysis of the BLi03719-encoding gene showed a high similarity with genes encoding the barnase of Bacillus amyloliquefaciens FZB42 and binase-like RNase of Bacillus pumilus SARF-032. The comparison of the control strain and a BLi03719-deficient strain revealed a strongly reduced extracellular ribonuclease activity of the mutant. Furthermore, this knockout mutant exhibited delayed growth with yeast RNA as an alternative phosphate and carbon source. These results suggest that BLi03719 is an extracellular ribonuclease expressed in B. licheniformis under phosphate starvation conditions. Finally, a BLi03719 mutant showed an advantageous effect on the overexpression of the heterologous amyE gene under phosphate-limited growth conditions.