1.The role of iron-uptake factor PiuB in pathogenicity of soybean pathogen Xanthomonas axonopodis pv. glycines.
Ruyi SU ; Luojia JIN ; Jiangling XU ; Huiya GENG ; Xiao CHEN ; Siyi LIN ; Wei GUO ; Zhiyuan JI
Chinese Journal of Biotechnology 2024;40(1):177-189
Iron is an essential element for living organisms that plays critical roles in the process of bacterial growth and metabolism. However, it remains to be elucidated whether piuB encoding iron-uptake factor is involved in iron uptake and pathogenicity of Xanthomonas axonopodis pv. glycines (Xag). To investigate the function of piuB, we firstly generated a piuB deletion mutant (ΔpiuB) by homologous recombination. Compared with the wild-type, the piuB mutant exhibited significantly reduced growth and virulence in host soybean. The mutant displayed markedly increased siderophore secretory volume, and its sensitivity to Fe3+, Cu2+, Zn2+ and Mn2+ was significantly enhanced. Additionally, the H2O2 resistance, exopolysaccharide yield, biofilm formation, and cell mobility of ΔpiuB were significantly diminished compared to that of the wild-type. The addition of exogenous Fe3+ cannot effectively restore the above characteristics of ΔpiuB. However, expressing piuB in trans rescued the properties lost by ΔpiuB to the levels in the wild-type. Taken together, our results demonstrated that PiuB is a potential factor for Xag to assimilate Fe3+, and is necessary for Xag to be pathogenic in host soybean.
Iron
;
Glycine max
;
Virulence
;
Xanthomonas axonopodis/genetics*
;
Hydrogen Peroxide
3.Clinical and molecular genetic study of nonketotic hyperglycinemia in a Chinese family.
Zhi-Jie GAO ; Qian JIANG ; Qian CHEN ; Ke-Ming XU
Chinese Journal of Contemporary Pediatrics 2017;19(3):268-271
Nonketotic hyperglycinemia (NKH) is a rare, inborn error of metabolism. In this case report, a Chinese male infant was diagnosed with NKH caused by GLDC gene mutation. The clinical characteristics and genetic diagnosis were reported. The infant presented with an onset of early metabolic encephalopathy and Ohtahara syndrome. Both blood and urinary levels of metabolites were in the normal range. Brain MRI images indicated a poor development of corpus callosum, and a burst suppression pattern was found in the EEG. Results of target gene sequencing technology combined with multiplex ligation-dependent probe amplification (MLPA) indicated a heterozygous missense mutation of c.1786 C>T (p.R596X) in maternal exon 15 and a loss of heterozygosity of 4-15 exon gross deletions in paternal GLDC gene. These definite pathogenic mutations confirmed the diagnosis of NKH. The infant's clinical condition was not improved after treatment with adreno-cortico-tropic-hormone, topiramate and dextromethorphan, and he finally died at 4 months of age. Patients with NKH often exhibit complicated clinical phenotypes and are lack of specific symptoms. NKH could be diagnosed by metabolic screening and molecular genetic analysis.
Glycine Dehydrogenase (Decarboxylating)
;
genetics
;
Humans
;
Hyperglycinemia, Nonketotic
;
diagnosis
;
genetics
;
Infant, Newborn
;
Male
;
Mutation
4.Silencing GmWRKY33B genes leads to reduced disease resistance in soybean.
Chenli ZHONG ; Wenxu WANG ; Lina LIAO ; Jianzhong LIU
Chinese Journal of Biotechnology 2024;40(1):163-176
The WRKYs are a group of plant-specific transcription factors that play important roles in defense responses. In this study, we silenced 2 GmWRKY33B homologous genes using a bean pod mosaic virus (BPMV) vector carrying a single fragment from the conserved region of the GmWRKY33B genes. Silencing GmWRKY33B did not result in morphological changes. However, significantly reduced resistances to Pseudomonas syringae pv. glycinea (Psg) and soybean mosaic virus (SMV) were observed in the GmWRKY33B-silenced plants, indicating a positive role of the GmWRKY33B genes in disease resistance. Kinase assay showed that silencing the GmWRKY33B genes significantly reduced the activation of GmMPK6, but not GmMPK3, in response to flg22 treatment. Reverse transcriptase PCR (RT-PCR) analysis of the genes encoding prenyltransferases (PTs), which are the key enzymes in the biosynthesis of glyceollin, showed that the Psg-induced expression of these genes was significantly reduced in the GmWRKY33B-silenced plants compared with the BPMV-0 empty vector plants, which correlated with the presence of the W-boxes in the promoter regions of these genes. Taken together, our results suggest that GmWRKY33Bs are involved in soybean immunity through regulating the activation of the kinase activity of GmMPK6 as well as through regulating the expression of the key genes encoding the biosynthesis of glyceollins.
Glycine max/genetics*
;
Disease Resistance/genetics*
;
Biological Assay
;
Dimethylallyltranstransferase
;
Gene Silencing
5.von Willebrand disease with G4022A mutation (vWd Sungnam): a case report.
Kyung Soon SONG ; Shin Heh KANG ; Myung Seo KANG ; Young Sook PARK ; Jong Rak CHOI ; Hyun Kyung KIM ; Quhen PARK
Journal of Korean Medical Science 1999;14(1):93-96
A 10-year-old male patient affected by type 2 von Willebrand disease (vWD) and his family members were investigated by hemostatic and molecular genetic studies. The propositus, who experienced frequent bleeding episodes, was characterized by a normal level of von Willebrand factor (vWF) antigen (54%), reduced vWF ristocetin cofactor activity (5%), decreased factor VIII clotting activity (25%) and absent high molecular weight multimers in the plasma. An exon 28 fragment coding for the A1 and A2 domains was amplified by polymerase chain reaction and sequenced. We found a heterozygous mutation (G4022A), producing an additional PstI restriction site, which resulted in the substitution of Arg578Gln. Family studies, including the parents and a brother, were negative for this mutation and vWF abnormalities were not observed. We confirmed that G to A mutation in the region of the platelet glycoprotein Ib binding domain of vWF causes the qualitative type 2 defect in von Willebrand disease.
Alanine/genetics*
;
Case Report
;
Child
;
Glycine/genetics*
;
Human
;
Male
;
Point Mutation*
;
von Willebrand Disease/genetics*
;
von Willebrand Factor/genetics*
6.Clinical and genetic analyses of a family with atypical nonketotic hyperglycinemia caused by compound heterozygous mutations in the GLDC gene.
Tie-Jia JIANG ; Jing-Jing JIANG ; Jia-Lu XU ; Jing ZHEN ; Pei-Fang JIANG ; Feng GAO
Chinese Journal of Contemporary Pediatrics 2017;19(10):1087-1091
Nonketotic hyperglycinemia (NKH) is an autosomal recessive hereditary disease caused by a defect in the glycine cleavage system and is classified into typical and atypical NKH. Atypical NKH has complex manifestations and is difficult to diagnose in clinical practice. This article reports a family of NKH. The parents had normal phenotypes, and the older brother and the younger sister developed this disease in the neonatal period. The older brother manifested as intractable epilepsy, severe spastic diplegia, intellectual disability, an increased level of glycine in blood and cerebrospinal fluid, an increased glycine/creatinine ratio in urine, and an increased ratio of glycine concentration in cerebrospinal fluid and blood. The younger sister manifested as delayed language development, ataxia, chorea, mental and behavior disorders induced by pyrexia, hypotonia, an increased level of glycine in cerebrospinal fluid, and an increased ratio of glycine concentration in cerebrospinal fluid and blood. High-throughput sequencing found a maternal missense mutation, c.3006C>G (p.C1002W), and a paternal nonsense mutation, c.1256C>G (p.S419X), in the GLDC gene in both patients. These two mutations were thought to be pathogenic mutations by a biological software. H293T cells transfected with these two mutants of the GLDC gene had a down-regulated activity of glycine decarboxylase. NKH has various phenotypes, and high-throughput sequencing helps to make a confirmed diagnosis. Atypical NKH is associated with the downregulated activity of glycine decarboxylase caused by gene mutations.
Child
;
Child, Preschool
;
Female
;
Glycine Dehydrogenase (Decarboxylating)
;
genetics
;
High-Throughput Nucleotide Sequencing
;
Humans
;
Hyperglycinemia, Nonketotic
;
genetics
;
Male
;
Mutation
7.SHMT1 C1420T polymorphism contributes to the risk of non-Hodgkin lymphoma: evidence from 7309 patients.
Yi-Wei WANG ; Shao-Dan ZHANG ; Wen-Ji XUE ; Mei-Ling ZHU ; Lei-Zhen ZHENG
Chinese Journal of Cancer 2015;34(12):573-582
BACKGROUNDSerine hydroxymethyltransferase 1 (SHMT1) is a key enzyme in the folate metabolic pathway that plays an important role in biosynthesis by providing one carbon unit. SHMT1 C1420T may lead to the abnormal biosynthesis involved in DNA synthesis and methylation, and it may eventually increase cancer susceptibility. Many epidemiologic studies have explored the association between C1420T polymorphism and the risk of non-Hodgkin lymphoma (NHL), but the results have been contradictory. Therefore, we performed this meta-analysis to evaluate the relationship.
METHODSThe meta-analyses were conducted to evaluate the effect of SHMT1 C1420T polymorphism on NHL risk. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to measure the strength of the association.
RESULTSEight studies encompassing 3232 cases and 4077 controls were included. A statistically significant association was found between SHMT1 C1420T polymorphism and NHL risk under the allelic comparison (T vs. C: OR = 1.09, 95% CI 1.01-1.17); a borderline association was found between SHMT1 C1420T polymorphism and NHL risk under the homozygote model (TT vs. CC: OR = 1.18, 95% CI 1.00-1.39) and the dominant model (CT+TT vs. CC: OR = 1.10, 95% CI 1.00-1.21).
CONCLUSIONSHMT1 C1420T polymorphism may be associated with NHL risk, which needs to be validated in large, prospective studies.
Case-Control Studies ; Evidence-Based Medicine ; methods ; Genetic Predisposition to Disease ; Glycine Hydroxymethyltransferase ; genetics ; Humans ; Lymphoma, Non-Hodgkin ; genetics ; Neoplasm Proteins ; genetics ; Polymorphism, Single Nucleotide ; Publication Bias ; Sensitivity and Specificity
8.Construction of co-expression SHMT and TPase recombinant vector and dual-enzymatic synthesis of L-tryptophan.
Xin LI ; Jun LIU ; Qinqin ZHAO ; Aicai XU
Chinese Journal of Biotechnology 2010;26(9):1302-1308
Hydroxymethyltransferase (SHMT) and tryptophanase (TPase) are key enzymes in biosynthesis of L-tryptophan. We constructed three recombinant plasmids, including pET-SHMT, pET-TPase, and pET-ST for over-expression or co-expression of SHMT and TPase in Escherichia coli BL21 (DE3). The SDS-PAGE analysis showed that the recombinant proteins of 47 kDa and 50 kDa were expressed of pET-SHMT and pET-TPase, respectively. As compared to the host stain, the enzyme activity of SHMT and TPase was increased by 6.4 and 8.4 folds, respectively. Co-expression of both recombinant proteins, 47 kDa and 50 kDa, was also successful by using pET-ST and the enzyme activities were enhanced by 6.1 and 6.9 folds. We designed two pathways of dual-enzymatic synthesis of L-tryptophan by using these recombinant strains as source of SHMT and TPase. In the first pathway, the pET-SHMT carrying strain was used to catalyze synthesis of L-serine, which was further transformed into L-tryptophan by the pET-TPase expressing strain. These two steps sequentially took place in different bioreactors. In the second pathway, the pET-ST carrying strain, in which two enzymes were co-expressed, was used to catalyze simultaneously two steps in a single bioreactor. HPLC analysis indicated a high yield of 41.5 g/L of L-tryptophan was achieved in the first pathway, while a lower yield of 28.9 g/L was observed in the second pathway. In the first pathway, the calculated conversion rates for L-glycine and indole were 83.3% and 92.5%, respectively. In the second pathway, a comparable conversion rate, 82.7%, was achieved for L-glycine, while conversion of indole was much lower, only 82.9%.
Escherichia coli
;
enzymology
;
genetics
;
metabolism
;
Gene Expression Regulation, Bacterial
;
physiology
;
Gene Expression Regulation, Enzymologic
;
physiology
;
Genetic Vectors
;
genetics
;
Glycine Hydroxymethyltransferase
;
biosynthesis
;
genetics
;
Plasmids
;
genetics
;
Recombinant Fusion Proteins
;
biosynthesis
;
genetics
;
pharmacology
;
Recombination, Genetic
;
genetics
;
Tryptophan
;
biosynthesis
;
Tryptophanase
;
biosynthesis
;
genetics
9.Conditions for protoplast preparation of spinosyn-producing strain and the physiological properties of protoplast-regenerated strains.
Yushuang LUO ; Xuezhi DING ; Liqiu XIA ; Hailong WANG ; Fan HUANG ; Ying TANG
Chinese Journal of Biotechnology 2009;25(3):360-367
To improve spinosyn-producing strain and enhance spinosyns yield, we studied the effects of glycin concentration and the operational time, temperature and lysozyme concentration on protoplast preparation of Saccharopolyspora spinosa SP06081. We also studied different regeneration media and osmotic stabilizing agents. In addition, we compared the change of morphology and spinosyns yield of the regenerated strains. The results showed that the Saccharopolyspora spinosa SP06081 protoplast yield was the highest under these conditions: the collected mycelium from SP06081 grown in Tryptic Soy Broth (TSB) medium with 0.2% glycin for 48 h was treated by 0.1 mg/mL lysozyme at 28 degrees C for 20 min, then plated on the R2YE medium with sucrose as osmotic stabilizer, the number of regeneration protoplast was up to 10(8)/mL. The protoplast-regenerated strains exhibited changes in morphology and antibiotic production, 29.3% protoplast-regenerated strains was characterized by loose mycelium and abundant broken branches as did their parent. Among them, 58.2% strains presented the trend to positive variation in spinosad yield, with the highest spinosad yield of up to 582.0 mg/L, 85.6% higher than that of their parent. There is significant correlation between the morphological differentiation and antibiotic yield of the protoplast-regenerated strains from spinosyn-producing strain.
Culture Media
;
pharmacology
;
Drug Combinations
;
Glycine
;
pharmacology
;
Insecticides
;
metabolism
;
Macrolides
;
metabolism
;
Muramidase
;
pharmacology
;
Protoplasts
;
cytology
;
drug effects
;
Regeneration
;
Saccharopolyspora
;
genetics
;
metabolism
;
physiology
10.Factors affecting transformation efficiency of BCG with a Mycobacterium-Escherichia coli shuttle vector pYUB18 by electroporation.
Sang Nae CHO ; Jin Hee HWANG ; Sun PARK ; Yunsup CHONG ; Sung Kyu KIM ; Chul Yong SONG ; Joo Deuk KIM
Yonsei Medical Journal 1998;39(2):141-147
BCG has been one of the vehicles for multi-recombinant vaccine. However, low transformation efficiency of BCG with plasmid DNA hampered studies involving expression of foreign antigens in BCG. In an effort to determine the optimal conditions, this study was initiated to investigate factors involved in the transformation of BCG with a Mycobacterium-Escherichia coli shuttle vector, pYUB18, by electroporation. Mycobacterium bovis BCG (strain 1173P2) was grown in Middlebrook (M) 7H9 broth containing albumin-dextrose-catalase and 0.05% tween 80, and transformed BCG was grown in M7H10 agar containing kanamycin for counting viable cells. Pretreatment of BCG with 10 mM CaCl2 improved the transformation efficiency, but overnight incubation of BCG with 1% glycine did not. The transformation efficiency in BCG also varied depending on voltage, resistance, and DNA concentration. The maximum transformation efficiency was obtained when the infinity resistance, 12.5 Kv/cm, and 100 ng of DNA were used, and reached 1.4 x 10(5) CFU/microgram of plasmid DNA, which is about 3-100 times greater than those from previous reports. The transformation conditions described in this study, therefore, will give us a better position for employing BCG as a vehicle for developing multi-recombinant vaccines.
Calcium Chloride/pharmacology
;
Comparative Study
;
DNA/metabolism
;
Electrophysiology
;
Electroporation*
;
Escherichia coli/genetics*
;
Genetic Vectors*
;
Glycine/pharmacology
;
Mycobacterium/genetics*
;
Mycobacterium bovis/genetics*
;
Osmolar Concentration
;
Transformation, Bacterial/physiology*
;
Transformation, Bacterial/drug effects