1.Expression and analysis of the recombinant human interleukin-21 (rhIL-21) in Pichia pastoris.
Dong LI ; Huiqing YU ; Rongfen HUO ; Jianquan CHEN ; Guoxiang CHENG
Chinese Journal of Biotechnology 2009;25(11):1711-1717
Interleukin-21 is a type I cytokine mainly produced by activated CD4+ T cells that acts as a regulator of immune system. In this work, hIL-21cDNA was amplified from human peripheral blood lymphocytes by RT-PCR, and then inserted into pPIC9K. The recombinant vector pPIC9K-hIL21cDNA was linearized by Sac I, and transformed into Pichia pastoris strain GS115 by electroporation. Transformants were selected by G418 and confirmed by PCR. The recombinant protein was expressed and secreted into the supernatant after inducing by methanol. SDS-PAGE analysis indicated the molecular weight of rhIL-21 was about 16 kD. ELISA results show that the yield of rhIL-21 reach 229.28 mg/L, rhIL-21 was purified from culture supernatants, and it was purified to about 95% purity with ion-exchange chromatography. When co-stimulate with Con A, rhIL-21 can promote the proliferation of human lymphocytes. This is the first expression of bio-active rhIL-21 in Pichia pastoris. It lays a foundation for further research in immunotherapy and cancer therapy.
Electroporation
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Genetic Vectors
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genetics
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Humans
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Interleukins
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biosynthesis
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genetics
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Pichia
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genetics
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metabolism
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Recombinant Proteins
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analysis
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biosynthesis
;
genetics
2.Localization of polypeptides release factors and ribosome protein L11 in Euplotes octocarinatus.
Baofeng CHAI ; Na LI ; Jingtao WANG ; Quan SHEN ; Zhiyun ZHANG ; Aihua LIANG
Chinese Journal of Biotechnology 2010;26(2):237-243
Protozoan ciliates are a group of unicellular eukaryotes. The special characteristics of stop codons usage in termination of protein biosynthesis in ciliates cells makes them an ideal model to study the mechanism of stop codon recognition of polypeptides release factors. To localize the functional positions of biomolecules in ciliates cell, we constructed a macronuclear artificial chromosome containing a gene encoding red fluorescence protein (EoMAC_R) based on the structural characteristics of ciliates chromosome. Three factors, L11, eRF1a, and eRF3 that are involved in termination process of protein synthesis were colocalized in Euplotes octocarinatus cells by using novel EoMAC_R and the previously constructed EoMAC_G. The results indicated that protein synthesis mainly occurred inside the "C" shape macronucleus, suggesting that EoMAC could be a useful tool for localizing biomolecules in ciliates cell.
Chromosomes, Artificial
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Codon, Terminator
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metabolism
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Euplotes
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chemistry
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Peptide Termination Factors
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analysis
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genetics
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metabolism
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Peptides
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metabolism
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Protein Biosynthesis
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genetics
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Protozoan Proteins
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analysis
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genetics
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Ribosomal Proteins
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analysis
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genetics
4.Expression of nesfatin-1/NUCB2 and ghrelin in gastric mucosa of rats with intrauterine growth retardation.
Ya-Ying CHENG ; Hong-Yan LV ; Xin WANG ; Guang-Yao SONG
Chinese Journal of Contemporary Pediatrics 2014;16(10):1051-1056
OBJECTIVETo investigate the expression of nesfatin-1/NUCB2 and ghrelin in the gastric mucosa of rats with intrauterine growth retardation (IUGR) and its significance.
METHODSThe IUGR animal model was established by feeding rats low-protein diets during their pregnancy. Newborn rats were divided into catch-up growth, non-catch-up growth and control groups. Protein and mRNA levels of nesfatin-1/NUCB2 and ghrelin in the gastric mucosa of rats were determined by RT-PCR and Western blot, respectively.
RESULTSNesfatin-1/NUCB2 mRNA and protein were expressed in the gastric mucosa of rats immediately after birth, and their expression increased in an age-dependent manner in all three groups. Furthermore, the level of nesfatin-1/NUCB2 in the catch-up growth group was higher than that in the control group before weaning, whereas there was no significant difference in nesfatin-1/NUCB2 expression between the two groups after weaning. The level of nesfatin-1/NUCB2 in the non-catch-up growth group was lower than that in the catch-up growth group during the whole observation period. The level of ghrelin in the catch-up growth group was higher than that in the control group starting from day 12 after birth, whereas there was no significant difference in ghrelin expression between the two groups after weaning. The level of ghrelin in the non-catch-up growth group was lower compared with those in the catch-up growth and control groups from days 12 to 28 after birth.
CONCLUSIONSNesfatin-1 and ghrelin are co-expressed in the gastric mucosa of rats with IUGR after birth and interact with each other to produce long-term nutritional regulation.
Age Factors ; Animals ; Calcium-Binding Proteins ; analysis ; genetics ; DNA-Binding Proteins ; analysis ; genetics ; Female ; Fetal Growth Retardation ; metabolism ; Gastric Mucosa ; chemistry ; Ghrelin ; analysis ; genetics ; Male ; Nerve Tissue Proteins ; analysis ; genetics ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley
5.Mutational Analysis of KRAS, BRAF, and TP53 Genes of Ovarian Serous Carcinomas in Korean Women.
Yun Hyun CHO ; Dae Yeon KIM ; Jong Hyeok KIM ; Yong Man KIM ; Kyu Rae KIM ; Joo Hyun NAM ; Young Tak KIM
Yonsei Medical Journal 2009;50(2):266-272
PURPOSE: To assess the prevalence of KRAS, BRAF, and TP53 mutations in cases of low-grade and high-grade serous carcinomas and to evaluate the clinical outcomes of these morphologically distinct carcinomas. MATERIALS AND METHODS: Patients with primary invasive serous carcinomas were classified according to the universal grading system. Grade 2 serous tumors were excluded. A total of 100 patients were included for clinical evaluation. Thirty-seven patients, including 20 with low-grade and 17 with high-grade carcinomas, were selected for mutational analysis. RESULTS: The low-grade carcinoma group was characterized by young age and premenopausal period compared with the high-grade carcinoma group, but there were no statistically significant differences in stage, metastasis of lymph node and residual disease. There were no statistically significant differences in survival rates, however, the low-grade carcinoma group showed a trend for improved progression-free survival compared with the high-grade carcinoma group of early stage (p = 0.064). Mutations in KRAS and BRAF were found in 6 (30%) and 2 (10%) patients in the low-grade carcinoma group, respectively, however, they were not found in the high-grade carcinoma group. KRAS and BRAF mutations were mutually exclusive, and both mutations were observed in 40% (8/20). The frequency of TP53 mutations in low-grade and high-grade carcinoma groups were found in 20% (4/20) and 70.6% (12/17), respectively (p = 0.009). CONCLUSION: Low-grade serous carcinoma shows mutation pattern different from that with high-grade carcinoma. As there were no significant differences in stage distribution and survival, especially in advanced stage, we suggest that more studies are needed to segregate these patients into distinct disease entities.
Adult
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Cystadenocarcinoma, Serous/*genetics
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DNA Mutational Analysis
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Female
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Humans
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Middle Aged
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Ovarian Neoplasms/*genetics
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Proto-Oncogene Proteins/*genetics
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Proto-Oncogene Proteins B-raf/*genetics
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ras Proteins/*genetics
6.Expression of Vitreoscilla hemoglobin improves recombinant lipase production in Pichia pastoris.
Xiaofeng WANG ; Yongchuan SUN ; Xuguang SHEN ; Feng KE ; Li XU ; Yun LIU ; Yunjun YAN
Chinese Journal of Biotechnology 2011;27(12):1755-1764
Yarrowia lipolytica lipase Lip2 (YlLip2) is an important industrial enzyme with many potential applications. To alleviate the dissolved oxygen (DO) limitation and improve YlLip2 production during high-cell density fermentation, the YlLip2 gene lip2 and Vitreoscilla hemoglobin (VHb) gene vgb were co-expressed in Pichiapastoris under the control of AOX1 and PsADH2 promoter, respectively. The PsADH2 promoter from Pichia stipitis could be activated under oxygen limitation. The SDS-PAGE and CO-difference spectrum analysis indicated that VHb and YlLip2 had successfully co-expressed in recombinant strains. Compared with the control cells (VHb-, GS115/9Klip2), the expression levels of YlLip2 in VHb-expressing cells (VHb+, GS115/9Klip2-pZPVT) under oxygen limitation were improved 25% in shake-flask culture and 83% in a 10 L fermentor. Moreover, the VHb+ cells displayed higher biomass than VHb- cells at lower DO levels in a 10 L fermentor. In this study, we also achieved a VHb-expressing clone harboring multicopy lip2 gene (GS115/9Klip2-pZPVTlip2 49#), which showed the maximum lipolytic activity of 33 900 U/mL in a 10 L fermentor under lower DO conditions. Therefore, it can be seen that expression of VHb with PsADH2 promoter in P. pastoris combined with increasing copies of lip2 gene is an effective strategy to improve YlLip2 production.
Bacterial Proteins
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biosynthesis
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genetics
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Fermentation
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Fungal Proteins
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biosynthesis
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genetics
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Lipase
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biosynthesis
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genetics
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Oxygen
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analysis
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pharmacology
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Pichia
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metabolism
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Protein Engineering
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Recombinant Proteins
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biosynthesis
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genetics
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Truncated Hemoglobins
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biosynthesis
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genetics
7.Analyses of Streptomyces coelicolor inner membrane proteome by multidimentional protein identification technology.
Xuan-Ming SHI ; Yuan-Ming LUO ; Gui-Feng ZHANG ; Zhi-Guo SU ; Yu-Bi HUANG ; Ke-Qian YANG
Chinese Journal of Biotechnology 2005;21(5):814-819
Streptomyces coelicolor is the model species among streptomycetes. Until now, proteomic analyses of S. coelicolor have been conducted using two-dimensional polyacrylamide gel electrophoresis and matrix-assisted laser desorption ionization time-of-flight mass spectrometry method, few integral membrane proteins were identified due to the hydrophobic and low-abundance nature of these proteins. In this work, 154 possible inner membrane proteins from S. coelicolor were identified using high pH-proteinase K sample preparation method and multidimensional protein identification technology, among them 44 are integral membrane proteins containing at least one transmembrane domain, most peptides and their corresponding proteins were identified experimentally for the first time.
Bacterial Proteins
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analysis
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Cell Membrane
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chemistry
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Genome, Bacterial
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genetics
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Mass Spectrometry
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methods
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Membrane Proteins
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analysis
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Proteome
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analysis
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genetics
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Streptomyces coelicolor
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chemistry
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genetics
8.Clinical features and PRRT2 gene mutation in paroxysmal kinesigenic dyskinesia.
Xiaoling YANG ; Yuehua ZHANG ; Xiaojing XU ; Zhixian YANG ; Shuang WANG ; Ye WU ; Xiru WU
Chinese Journal of Pediatrics 2015;53(8):621-625
OBJECTIVETo investigate the clinical features and proline-rich transmembrane protein 2 (PRRT2) gene mutation in patients with paroxysmal kinesigenic dyskinesia (PKD).
METHODClinical information was collected at Peking University First Hospital from January 2004 to July 2014. In total, 10 patients with PKD were recruited, and all were males. Among them, four patients were the probands from four PKD families and the other six patients were sporadic cases. Clinical information was analyzed. Peripheral blood samples for DNA study were collected from PKD patients and their family members. Genomic DNA was extracted using standard procedures. Mutation analysis of PRRT2 was performed by Sanger sequencing after PCR.
RESULTOf the 10 patients, the median age of dyskinesias onset was 10 years, ranging from 4 to 13 years. The description of their attacks were abnormal involuntary movements provoked by sudden movements, without loss of consciousness. Five patients exhibited dystonia, two patients exhibited choreoathetosis, and three patients had mixed (dystonia and choreoathetosis) dyskinesias. The duration of the attacks lasted for 3 to 30 seconds. The frequency ranged from once per month to twenty times per day. PRRT2 mutations, c. 649_650insC (p. R217PfsX8), were found in all the four PKD families. Mutation c. 649_650insC was also detected in two of the six sporadic PKD cases, inheriting from their asymptomatic mother.
CONCLUSIONThe onset age of PKD could be in the early childhood. The clinical features of the familial cases and sporadic cases showed no difference. The attacks manifested as dystonia, choreathetosis, or mixed. PRR2 mutations could be identified in familial or sporadic cases with PKD. Mutation c. 649_650insC is the hotspot mutation of PRRT2 gene.
Adolescent ; Child ; Child, Preschool ; DNA Mutational Analysis ; Dystonia ; genetics ; Humans ; Male ; Membrane Proteins ; genetics ; Mutation ; Nerve Tissue Proteins ; genetics
10.Identification of active efflux system gene qacA/B in methicillin-resistant Staphylococcus aureus and its significance.
Rong ZHENG ; Min WANG ; Bin HE ; Xianping LI ; Hong CAO ; Hao LIANG ; Zhiju QING ; Aiguo TANG
Journal of Central South University(Medical Sciences) 2009;34(6):537-542
OBJECTIVE:
To detect the active efflux gene qac gene in methicillin-resistant Staphylococcus aureus (MRSA) by hem-nested polymerase chain reaction (PCR) and to learn the carrier condition of qac gene.
METHODS:
The active efflux gene qacA/B and qacB of 80 strains MRSA isolated from clinical specimens from Aug 2006 to March 2008 were amplified in vitro by hem-nested PCR with the primers designed by computers based on qac information of Genbank, and the PCR fragments were sequenced and analyzed.
RESULTS:
We detected qacA/B in 19 out of the 80 MRSA strains (23.75%) and qacB in 18 out of the 80 MRSA strains (22.5%). Compared with sequences of qacA (NO.X56628) and qacB(NO.AF535087) in the Genbank, 98% and 97% were identical, respectively.
CONCLUSION
The active efflux gene qac gene in MRSA is detected by hem-nested PCR. The proportion of qac gene positive strains is high in clinical practice, which is related to its multi-antibiotic resistance.
Bacterial Proteins
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analysis
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genetics
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Base Sequence
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Drug Resistance, Multiple
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genetics
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Membrane Transport Proteins
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analysis
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genetics
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Methicillin-Resistant Staphylococcus aureus
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genetics
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Molecular Sequence Data
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Polymerase Chain Reaction
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methods