OBJECTIVE: By analyzing the correlation between genotypes and phenotypes, we explored the impact of the variant c.917T>C (p.L306P) in the ABO*B.01 allele on the expression and function of B-glycosyltransferase (GTB). This study aims to elucidate the molecular mechanisms underlying the occurrence of this subtype. METHODS: The study subjects included a blood donor specimen with incompatible forward and reverse ABO typing results. ABO phenotyping was determined using ABO blood group serology and GTB activity testing. Subsequently, Sanger sequencing and third-generation sequencing based on the PacBio platform were employed to sequence the ABO gene, resulting in the determination of haplotype sequences. Mutations were identified through sequence alignment. An in vitro cell expression system was established to assess the impact of the mutation site on antigen expression. RESULTS: The index case in this study was identified as B subtype with the allelic genotype c.917T>C in ABO*B.01/ABO*O.01.01 , which has not been previously reported. in vitro expression results revealed decreased levels of GTB expression and overall GTB activity in the mutant cells. Furthermore, the expression of the B antigen on the cell membrane was weaker in the mutant cells compared to the wild-type cells. CONCLUSION The p.L306P variation caused by the c.917T>C mutation in the ABO*B.01 allele may be a genetic factor contributing to the reduced expression of B antigens on the surface of red blood cells.
Humans ; ABO Blood-Group System/genetics* ; Alleles ; Genotype ; Mutation ; Glycosyltransferases/genetics* ; Haplotypes ; Phenotype

OBJECTIVE: To analyze the B_el subtype gene mutation and its genetic mechanism in a family line. METHODS: ABO blood groups were identified by serologic tests. ABO genotyping was performed by polymerase chain reaction with sequence-specific primer (PCR-SSP). Sanger sequencing was performed on exons 1-7 of the ABO gene, the flanking intronic region, and exon 7 of the single strand of the gene confirmed the mutation site location. Missense3D software was used to predict the protein structure alteration caused by this mutation. RESULTS: Conventional serologic tests failed to detect erythrocyte B antigen in the proband and her three family members, and only trace amounts of B antigen expression could be detected by the absorption-dispersal test. DNA analysis showed that, on the basis of the normal ABO gene, there was a G>T substitution in the position of exon 7, position 803, which resulted in the change of amino acid 268 from Gly to Val. Further single-stranded sequencing analysis showed that the mutation site was located in the B gene. CONCLUSION In this family line, the proband, her father, her son, and her daughter all have reduced B type glycosyltransferase activity due to the new point mutation (c.803G>T) in exon 7 of the B gene, and the B antigen can only be detected by the absorption-dispersal method, and the point mutation can be stably inherited by offspring.
Point Mutation ; Alleles ; ABO Blood-Group System/genetics* ; Exons ; Introns ; Genotype ; Humans ; Male ; Female ; Glycosyltransferases/genetics*

OBJECTIVE: The molecular biology of alleles of ABO blood group A_el and B_el subtype from two samples was analyzed to explore the effect of mutations on the structure of glycosyltransferase. METHODS: The ABO phenotypes were identified by serological techniques, then exons 6 and 7 of ABO gene were amplified and sequenced, combined with haplotype analysis to determine the genotypes. Finally, homology modeling of the mutated A/B glycosyltransferase were conducted by Modeller software and the effect of mutations on the spatial structure was analyzed by PyMol software. RESULTS: The serological phenotypes of the two samples were A_el and B_el, and their genotypes were ABO*AW.37/ABO*O.01.01 and ABO*BEL.03/ABO*O.01.01, respectively. The three-dimensional structure modeling of the protein showed that, compared to the wild-type glycosyltransferase, two hydrogen bonds between the side chain of p.Glu314 and surrounding amino acid disappeared in the p.Lys314Glu mutant GTA; the hydrogen bonds between the side chain of p.Trp168 and surrounding amino acid also disappeared, and the hydrogen bond between the main chain of p.Trp168 and p.Gly165 was shortened to 3.3 Å in the p.Arg168Trp mutant GTB. CONCLUSION Mutations in exon 7 of ABO gene c.940A>G and c.502C>T are keys to the formation of AW.37 and BEL.03 alleles, resulting in decreased expression of A and B antigens, respectively.
ABO Blood-Group System/classification* ; Humans ; Genotype ; Mutation ; Alleles ; Glycosyltransferases/genetics* ; Exons ; Haplotypes ; Phenotype ; Models, Molecular

Traditional Chinese medicine of Polygonum cuspidatum has been utilized in China for thousands of years. Its primary active compound, polydatin, exhibits a variety of pharmacological effects including the regulation of glucose and lipid metabolism, suppression of cough and asthma, as well as antibacterial and anti-inflammatory properties. However, conventional methods for polydatin production are inadequate to satisfy the market demand. This study aims to explore the green and efficient preparation of polydatin. With resveratrol as the substrate, we efficiently synthesized polydatin by using the triple mutant IGW (Y14I/I62G/M315W) of the glycosyltransferase UGT_BS based on a strategy of two-enzyme coupled with one-pot and realized the recycling of uridine diphosphate-glucose (UDPG). The conditions of the two-enzyme reaction were optimized. Under the conditions of 35 ℃, pH 8.0, IGW: AtSuSy1 activity ratio of 3:4, dimethyl sulfoxide (DMSO) volume fraction of 5%, uridine diphosphate (UDP) concentration of 0.10 mmol/L, and sucrose concentration of 0.6 mol/L, the conversion of 2 mmol/L resveratrol reached 80.6% within 1 h, and the proportion of polydatin was over 90%. This study achieved the recycling of UDPG via a two-enzyme coupling system and shortened the reaction time. At the same time, the fed-batch strategy was adopted, and the yield of polydatin reached 6.28 g/L after 24 h in the one-pot coupling reaction, which provided a new strategy for green and efficient preparation of polydatin.
Stilbenes/chemistry* ; Glucosides/biosynthesis* ; Resveratrol ; Fallopia japonica/chemistry* ; Glycosyltransferases/genetics*

Carthami Flos, as a traditional blood-activating and stasis-resolving drug, possesses anti-tumor, anti-inflammatory, and immunomodulatory pharmacological activities. Flavonoid glycosides are the main bioactive components in Carthamus tinctorius. Glycosyltransferase deserves to be studied in depth as a downstream modification enzyme in the biosynthesis of active glycoside compounds. This study reported a flavonoid glycosyltransferase CtUGT49 from C. tinctorius based on the transcriptome data, followed by bioinformatic analysis and the investigation of enzymatic properties. The open reading frame(ORF) of the gene was 1 416 bp, encoding 471 amino acid residues with the molecular weight of about 52 kDa. Phylogenetic analysis showed that CtUGT49 belonged to the UGT73 family. According to in vitro enzymatic results, CtUGT49 could catalyze naringenin chalcone to the prunin and choerospondin, and catalyze phloretin to phlorizin and trilobatin, exhibiting good substrate versatility. After the recombinant protein CtUGT49 was obtained by hetero-logous expression and purification, the enzymatic properties of CtUGT49 catalyzing the formation of prunin from naringenin chalcone were investigated. The results showed that the optimal pH value for CtUGT49 catalysis was 7.0, the optimal temperature was 37 ℃, and the highest substrate conversion rate was achieved after 8 h of reaction. The results of enzymatic kinetic parameters showed that the K_m value was 209.90 μmol·L~(-1) and k_(cat) was 48.36 s~(-1) calculated with the method of Michaelis-Menten plot. The discovery of the novel glycosyltransferase CtUGT49 is important for enriching the library of glycosylation tool enzymes and provides a basis for analyzing the glycosylation process of flavonoid glycosides in C. tinctorius.
Carthamus tinctorius/chemistry* ; Phylogeny ; Flavonoids/analysis* ; Glycosides/analysis* ; Glycosyltransferases/genetics* ; Anti-Inflammatory Agents ; Chalcones

Uridine diphosphate glycosyltransferase(UGT) is a highly conserved protein in plants, which usually functions in secondary metabolic pathways. This study used the Hidden Markov Model(HMM) to screen out members of UGT gene family in the whole genome of Dendrobium officinale, and 44 UGT genes were identified. Bioinformatics was used to analyze the structure, phylogeny, and promoter region components of D. officinale genes. The results showed that UGT gene family could be divided into four subfamilies, and UGT gene structure was relatively conserved in each subfamily, with nine conserved domains. The upstream promoter region of UGT gene contained a variety of cis-acting elements related to plant hormones and environmental factors, indicating that UGT gene expression may be induced by plant hormones and external environmental factors. UGT gene expression in different tissues of D. officinale was compared, and UGT gene expression was found in all parts of D. officinale. It was speculated that UGT gene played an important role in many tissues of D. officinale. Through transcriptome analysis of D. officinale mycorrhizal symbiosis environment, low temperature stress, and phosphorus deficiency stress, this study found that only one gene was up-regulated in all three conditions. The results of this study can help understand the functions of UGT gene family in Orchidaceae plants and provide a basis for further study on the molecular regulation mechanism of polysaccharide metabolism pathway in D. officinale.
Dendrobium/genetics* ; Plant Growth Regulators ; Glycosyltransferases/metabolism* ; Gene Expression Profiling ; Mycorrhizae ; Phylogeny ; Plant Proteins/metabolism*

In this study, the authors cloned a glycosyltransferase gene PpUGT2 from Paris polyphylla var. yunnanensis with the ORF length of 1 773 bp and encoding 590 amino acids. The phylogenetic tree revealed that PpUGT2 belonged to the UGT80A subfamily and was named as UGT80A49 by the UDP-glycosyltransferase(UGT) Nomenclature Committee. The expression vector pET28a-PpUGT2 was constructed, and enzyme catalytic reaction in vitro was conducted via inducing protein expression and extraction. With UDP-glucose as sugar donor and diosgenin and pennogenin as substrates, the protein was found with the ability to catalyze the C-3 hydroxyl β-glycosylation of diosgenin and pennogenin. To further explore its catalytic characteristic, 15 substrates including steroids and triterpenes were selected and PpUGT2 showed its activity towards the C-17 position of sterol testosterone with UDP-glucose as sugar donor. Homology modelling and molecule docking of PpUGT2 with substrates predicted the key residues interacting with ligands. The re-levant residues of PpUGT2-ligand binding model were scanned to calculate the corresponding mutants, and the optimized mutants were obtained according to the changes in binding affinity of the ligand with protein and the surrounding residues within 5.0 Å of ligands, which had reference value for design of the mutants. This study laid a foundation for further exploring the biosynthetic pathway of polyphyllin as well as the structure of sterol glycosyltransferases.
Ligands ; Glycosyltransferases/genetics* ; Sterols ; Phylogeny ; Ascomycota ; Liliaceae/chemistry* ; Melanthiaceae ; Diosgenin ; Sugars ; Glucose ; Uridine Diphosphate

OBJECTIVE: To explore the serological characteristics of ABO blood group and molecular genetic mechanism for a Chinese pedigree with cisAB09 subtype. METHODS: A pedigree undergoing ABO blood group examination at the Department of Transfusion, Zhongshan Hospital Affiliated to Xiamen University on February 2, 2022 was selected as the study subjects. Serological assay was carried out to determine the ABO blood group of the proband and his family members. Activities of A and B glycosyltransferases in the plasma of the proband and his mother were measured with an enzymatic assay. Expression of A and B antigens on the red blood cells of the proband was analyzed by flow cytometry. Peripheral blood samples of the proband and his family members were collected. Following extraction of genomic DNA, exons 1 to 7 of the ABO gene and their flanking introns were sequenced, and Sanger sequencing of exon 7 was carried out for the proband, his elder daughter and mother. RESULTS: The results of serological assay suggested that the proband and his elder daughter and mother had an A2B phenotype, whilst his wife and younger daughter had an O phenotype. Measurement of plasma A and B glycosyltransferase activity suggested that the titers of B-glycosyltransferase activity were 32 and 256 for the proband and his mother, which were respectively below and above that of A1B phenotype-positive controls (128). Flow cytometry analysis showed that the expression of A antigen on the red blood cell surface of the proband has decreased, whilst the expression of B antigen was normal. Genetic sequencing confirmed that, in addition to an ABO*B.01 allele, the proband, his elder daughter and mother have harbored a c.796A>G variant in exon 7, which has resulted in substitution of the methionine at 266th position of the B-glycosyltransferase by valine and conformed to the characteristics of ABO*cisAB.09 allele. The genotypes of the proband and his elder daughter were determined as ABO*cisAB.09/ABO*O.01.01, his mother was ABO*cisAB.09/ABO*B.01, and his wife and younger daughter were ABO*O.01.01/ABO*O.01.01. CONCLUSION The c.796A>G variant of the ABO*B.01 allele has resulted in an amino acid substitution p.Met266Val, which probably underlay the cisAB09 subtype. The ABO*cisA B.09 allele encodes a special glycosyltransferase which can synthesize normal level of B antigen and low level of A antigen on the red blood cells.
Humans ; ABO Blood-Group System/genetics* ; Pedigree ; East Asian People ; Genotype ; Phenotype ; Alleles ; Glycosyltransferases/genetics* ; Molecular Biology

The lignan glycosyltransferase UGT236(belonging to the UGT71 B family) from Isatis indigotica can catalyze the production of phloridzin from phloretin in vitro. UGT236 shares high identity with P2'GT from apple. In this study, the recombinant plasmid pET28 a-MBP-UGT236 was transferred into Escherichia coli Rosetta(DE3) cells and induced by isopropyl-β-D-thiogalactoside(IPTG). The purified UGT236 protein was used for enzymatic characterization with phloretin as substrate. The results showed that UGT236 had the optimal reaction temperature of 40 ℃ and the optimal pH 8(Na_2HPO_4-NaH_2PO_4 system). The UGT236 activity was inhibited by Ni~(2+) and Al~(3+), enhanced by Fe~(2+), Co~(2+), and Mn~(2+), and did not affected by Mg~(2+), Ca~(2+), Li~+, Na~+, or K~+. The K_m, K_(cat), and K_(cat)/K_m of phloretin were 61.03 μmol·L~(-1), 0.01 s~(-1), and 157.11 mol~(-1)·s~(-1)·L, and those of UDPG were 183.6 μmol·L~(-1), 0.01 s~(-1), and 51.91 mol~(-1)·s~(-1)·L, respectively. The possible active sites were predicted by homologous modeling and molecular docking. By mutagenisis and catalytic activity detection, three key active sites, Glu391, His15, and Thr141, were identified, while Phe146 was related to product diversity. In summary, we found that the lignan glycosyltransferase UGT236 from I.indigotica could catalyze the reaction of phloretin into phloridzin. Several key amino acid residues were identified by structure prediction, molecular docking, and site-mutagenesis, which provided a basis for studying the specificity and diversity of phloretin glycoside products. This study can provide a reference for artificially producing glycosyltransferase elements with high efficiency and specific catalysis.
Glucosyltransferases/genetics* ; Glycosyltransferases/metabolism* ; Isatis ; Lignans/metabolism* ; Molecular Docking Simulation ; Phloretin/metabolism* ; Phlorhizin/metabolism*

OBJECTIVE: To explore the genetic basis of three children with unexplained mental retardation/developmental delay. METHODS: Peripheral venous blood samples were collected for routine G-banding karyotyping analysis and chromosomal microarray analysis (CMA). Whole exome sequencing (WES) was also carried out for patient 3. RESULTS: The karyotypes of the 3 children were normal. The result of CMA analysis of patient 1 was arr[GRCh37]: 2q22/3(145 128 071-145 159 029)×1, with a 31 kb deletion, which was predicted to be a pathogenic copy number variation. The deletion has involved exons 8 to 10 of the ZEB2 gene. Patient 2 was arr[hg19]:2q22.3 (145 071 457-146 881 759)×1, with a 1.81 Mb deletion involving the ZEB2 and GTDC1 genes. Patient 3 was arr[GRCh37]: 9p23p23(11 698 261-12 106 261)×1, with a 408 kb deletion containing no disease-associated gene. WES has identified a c.2102C>A (p.Ser701*) variant in exon 8 of the ZEB2 gene, which was included in ClinVar database and rated as pathogenic, and verified by Sanger sequencing as a de novo variant. CONCLUSION For the substantial clinical and genetic heterogeneity of Mowat-Wilson-syndrome, CMA and WES are helpful to identify the etiology of children with developmental delay/mental retardation of unknown causes, particularly those with peculiar facial features and multiple congenital malformations.
Child ; DNA Copy Number Variations ; Facies ; Glycosyltransferases/genetics* ; Hirschsprung Disease ; Humans ; Intellectual Disability/genetics* ; Microcephaly/genetics*