Search

[Objective] In order to improve the yield of prodigiosin, the fermentation conditions of a strain of Klebsiella oxytoca P3 isolated and preserved in the laboratory to produce prodigiosin were optimized. [Method] The composition and molecular weight of the extract were analyzed by liquid chromatography-mass spectrometry (LC-MS), and the fermentation conditions (temperature, pH, NaCl concentration, inducing sugar) of P3 were studied by shaking flask culture. [Result]The red pigment produced by fermentation culture was proved to be prodigiosin by LC-MS analysis, with a molecular weight of 324. 27. The optimum fermentation conditions for P3 production of prodigiosin were determined as follows:24 ℃, pH 7. 2-8. 0, NaCl concentration 0. 05%-0. 10%, 2% fructose induction. [Conclusion] The fermentation product of Klebsiella P3 was prodigiosin, and the optimized yield of prodigiosin was 90-130 mg / L. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】The sequence characteristics, including the physical-chemical properties, structure and homology relationship, of pectin acid lyase K-PGL of Klebsiella sp. were analyzed. 【Method】The primers were designed according to the homologous K-PGL gene sequence, and the gene was obtained by PCR and Genome Walking technology. The signal peptide, hydrophobicity and structural domain of gene were analyzed. 【Result】A total of 2395 bp sequences of Klebsiella sp. were obtained. The open reading frame of K-PGL gene was 1710 bp, encoding 569 amino acids. The molecular mass and the isoelectric point of K-PGL was 63.37 kDa and 7.17, respectively. A signal peptide cleavage site with an efficiency of 0.864 was found existing in the K-PGL. There was no Cysteine in the K-PGL, and the hydrophobic index was-0.449, which indicated that K-PGL was a stable existing protein. The K-PGL had a conserved domain unique to the endo-galacturonic acid lyase family, and was most close with Klebsiella oxytoca. 【Conclusion】The sequence and characteristics of K-PGL gene were obtained in article, which would promote the further study of the function and application of pectin lyase. [ABSTRACT FROM AUTHOR]

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objectives: To explore the mechanisms of imipenem resistance in Klebsiella spp. and the transmission of Klebsiella pneumoniae Carbapenemase-2( KPC -2) gene in Klebsiella species., Methods: The imipenem resistant Klebsiella pneumoniae and Klebsiella oxytoca were isolated in the West China Hospital of Sichuan University in 2009/2010 and 2012/2013. Their minimal inhibitory concentration (MIC) was determined by agar dilution method. CARB ChromID plate and improved Hodge test were undertaken to detect carbapenemases resistant phenotype. PCR method was used for detecting KPC-2 gene. Plasmid transmission was detected by plasmid conjugation tests. The homology of the plasmids and the strains was analyzed using random amplified polymorphic DNA (RAPD) and enterobacterial repetitive intergenic consensus PCR(ERIC-PCR) methods., Results: Three strains of Klebsiella oxytoca collected in 2009/2010 and 7 Klebsiella pneumoniae collected in 2012/2013 developed carbapenemases resistance, all of which carried KPC -2 gene. The 3 KPC -2 positive plasmids isolated from Klebsiella oxytoca transited to recipient organisms and showed homology with the 7 KPC -2 gene positive plasmids isolated from Klebsiella pneumoniae . The ERIC-PCR showed homology of the 7 KPC positive Klebsiella pneumoniae ., Conclusions: Carbapenemases in Klebsiella spp with expressed KPC -2 gene contribute to the development of resistance in this hospital. The transmission of KPC -2 plasmid in Klebsiella oxytoca may cause imipenem resistance in Klebsiella pneumonia . The horizontal transmission may be the main mechanism in the spread of imipenem resistance in Klebsiella spp .

Cadaverine is a biogenic amine that has the potential to become an important platform chemical for the production of industrial polymers, such as polyamides and polyurethanes. We reported here a lysine decarboxylase from Klebsiella oxytoca. The lysine decarboxylase from Klebsiella oxytoca was cloned to Escherichia coli to get the strain LN18. The specific activity of the crude protein from LN18 reached 30 000 U. The molecular weight was about 80 kDa. The optimum temperature and pH of the crude protein were 55 ℃ and 5.5 respectively. The specific activity could keep over 30% at pH 8.0 compared the one at pH 5.5, much difference from Escherichia coli lysine decarboxylase CadA. Mg²⁺ was positive to the specific activity, whereas Fe²⁺, Zn²⁺ and Ca²⁺ were negative.