Protein A and protein G are two well-defined immunoglobulin (Ig)-binding proteins (IBPs), which show affinity for specific sites on Ig of mammalian hosts. Protein A and protein G contained several highly homologous IgG-binding domains which had been demonstrated to have function to bind to IgG. Whether combinations of Ig-binding domains of various IBPs could produce useful novel binding properties remains interesting. We constructed a combinatorial phage library which displayed randomly-rearranged A, B, C, D and E domains of protein A, B2 and B3 domains of protein G. Four rounds molecular evolution of this library directed by all four human IgG subclasses respectively generated a common arrangement of D-C respectively which didn't exist in SpA. The dynamic loss of control phages and increase of the phages displaying two or more binding domains, especially the selective enrichment of D-C and strict selection of its linking peptides demonstrated the efficient molecular evolutions and the significance of the selected D-C arrangement. The phage binding assays confirmed that D-C possessed a binding advantage with four human IgG subclasses compared to SpA. In this work, a novel combination of Ig-binding domains, D-C, was obtained and presented the novel Ig binding properties which provided a novel candidate molecule for the purification, production and detection of IgG antibodies and a new approach for the further study of structures and functions of IBPs.
Amino Acid Sequence ; Antibody Specificity ; Bacterial Proteins ; immunology ; metabolism ; Binding Sites ; Binding, Competitive ; Evolution, Molecular ; Immunoglobulin G ; immunology ; metabolism ; Molecular Sequence Data ; Peptide Library ; Sequence Alignment ; Staphylococcal Protein A ; immunology ; metabolism

HLA-A24 is the second most frequently expressed HLA-A type in Koreans (GF 22.8%). Four different serologic reaction patterns were observed in Korean A24 positive samples using a commercial serologic typing kit. To clarify the nature of serologic heterogeneity, thirteen A24 positive DNA samples representing the four different serologic reaction patterns were subjected to DNA sequencing analysis of the amplified HLA-A genes from each sample. Four A*24 alleles (A*2402101, A*2403, A*2408, and A*2421) were associated with the four unique serologic reaction patterns. During this study, a novel allele, A*2421, was characterized. The new sequence is similar to A*2402101, differing at codon 127 (AAA-->AAC; K-->N). By comparing putative amino acid sequences and serologic reaction patterns of A*24 allelic products identified in this study, several crucial sites for A24- and A9-specific antibody binding were predicted: 127K for A24 antibody binding, and 62E-65G and 166D-167G for A9 antibody binding. This information will be helpful for accurately assigning HLA-A24 types by serology and for predicting serologic types of new alleles.
Alleles ; Base Sequence ; Binding Sites, Antibody ; DNA, Complementary ; Female ; Genetic Heterogeneity ; HLA-A Antigens/immunology* ; HLA-A Antigens/genetics* ; Human ; Korea ; Male ; Molecular Sequence Data ; Pedigree

Antibody drug conjugates (ADCs) are an emerging class of targeted therapeutics with the potential to improve therapeutic index over the traditional chemotherapy. However, it is difficult to control the site and stoichiometry of conjugation in mAb, typically resulting in heterogeneous mixtures of ADCs that are difficult to optimize. New methods for site-specific drug attachment allow development of more homogeneous conjugates and control of the site of drug attachment. In this article, the new literature on development of ADCs and site-specific ADCs is reviewed. In addition, we summarized the various strategies in production of site-specific ADCs.
Antibodies, Monoclonal ; chemistry ; Antibody Specificity ; Binding Sites, Antibody ; Immunoconjugates ; chemistry

Premature ejaculation (PE) is a most common male sexual dysfunction with complex pathogenesis. An increasing number of scholars agree that PE is a disorder associated with abnormal neurobiology, which involves the central neurotransmitter system, peripheral nerve function of the nerve tissue structure, and neurological biochemistry. This review focuses on the neurobiological mechanisms of PE, expecting to gain a deeper insight into the possible etiology, objective and reliable diagnostic methods, and individualized treatment of the disease.
Biochemical Phenomena ; Ejaculation ; Humans ; Male ; Neurotransmitter Agents ; physiology ; Peripheral Nervous System ; physiopathology ; Premature Ejaculation ; etiology

OBJECTIVETo identify the IgE-binding epitopes in the allergen Der p 1 of main house dust mites, which can be recognized by the specific IgE in the sera from allergic individuals, and obtain a hypoallergen derived from the T-B epitope fused peptide for potential use in specific immunotherapy (SIT).

METHODSThirty-one peptides containing 15 amino acids each, which covered the full 222 amino acids of Der p 1 protein sequence, were synthesized on the cellulous membrane by solid-phase peptide (SPOTs) synthesis, with 8 overlapping amino acids between every two neighboring peptides. The membrane bearing the spots of the synthesized peptides were incubated with the allergic serum pools consisting of the sera from 5 allergic individuals. The membrane was then probed with HRP-conjugated anti-human IgE, followed by enhanced chemiluminescence (ECL) for visualization and gray scale analysis of the positive peptide spots.

RESULTSThree strong IgE-binding epitopes were identified in the amino acid sequence of Der p 1 molecule, namely Ep1 (amino acids 85-99), Ep2 (amino acids 106-120) and Ep3 (amino acids 190-204).

CONCLUSIONThe 3 IgE-binding epitopes (B cell epitopes) identified in Der p 1 confirm the presence of linear epitopes in Der p 1, suggesting the possibility of constructing T/B epitope-fused hypoallergens.

Amino Acid Sequence ; Animals ; Antigens, Dermatophagoides ; immunology ; Arthropod Proteins ; immunology ; Binding Sites, Antibody ; Cysteine Endopeptidases ; immunology ; Epitopes ; immunology ; Immunoglobulin E ; immunology ; Lymphokines ; immunology ; Mites ; immunology ; Molecular Sequence Data

PURPOSE: We investigated the biochemical characteristics of serum and urine in the patients suffering with uric acid stone. MATERIALS AND METHODS: A total of 99 patients suffering with uric acid stone underwent routine urine analysis and 24-hour urine analysis for determining the urinary calculi risk factors. We conducted serum analysis for the stone risk factors and also analysis of the stone analysis. To compare the stone risk factors, 93 patients with calcium stone were identified and then the biochemical risk factors in the serum and urine were evaluated. RESULTS: The mean age of patients with uric acid stone was 56.5+/-12.4 years and the mean age of the patients with calcium stone was 40.2+/-11.5 years. Serum uric acid, cholesterol and triglyceride were all significantly increased in the patients with uric acid stone compared to that in the patients with calcium stone. The patients with uric acid stone showed a lower urinary pH and also lower urinary uric acid and citric acid excretion compared with those patients with calcium stone. The composition of the uric acid stone was mixed with calcium in 63.6 percent of the stones and 36.4% of the stones were pure. CONCLUSIONS: The patients with uric acid stone had higher serum uric acid, cholesterol and triglyceride, and they had a lower urinary pH and lower uric acid and citric acid excretion as compared with the patients with calcium stone. Uric acid-calcium mixed stone was most common in the patients with uric acid stone. There is a great likelihood of uric acid stone in the patients with stone who have one or more of the above mentioned biochemical characteristics. Therefore, these factors are important to conduct metabolic evaluation for preventing stone recurrence.
Biochemical Phenomena ; Calcium ; Cholesterol ; Citric Acid ; Humans ; Hydrogen-Ion Concentration ; Population Characteristics ; Recurrence ; Risk Factors ; Triglycerides ; Uric Acid* ; Urinary Calculi

Biochemical Phenomena ; Exercise ; Humans ; Inflammation ; metabolism ; Massage ; methods ; NF-kappa B ; metabolism ; Reproducibility of Results ; Transcription Factors ; metabolism

Base Sequence ; Binding Sites, Antibody ; Biochemistry ; methods ; Electrophoresis, Polyacrylamide Gel ; Enzyme-Linked Immunosorbent Assay ; Escherichia coli ; genetics ; Genetic Vectors ; Immunoglobulin Fc Fragments ; genetics ; metabolism ; Immunoglobulin G ; genetics ; metabolism ; Ligands ; Molecular Sequence Data ; Plasmids ; Protein Binding ; Recombinant Fusion Proteins ; genetics ; isolation & purification ; Staphylococcal Protein A ; genetics ; metabolism

With the development of systemic diagnostic technique in cancer, the diagnostic methods of head and neck region are developing, also. Now, it is usually used computed tomography(CT), magnetic resornance image(MRI) in head and neck cancer and positron emission tomography(PET) is being increased in diagnostic use because of tumor specificity and accuracy. However, CT and MRI show the advantage of showing precise anatomical landmarks, but the disadvantage of these methods is much affecting by anatomical variations and changes. Otherwise, PET presents the imaging of physiologic and biochemical phenomenon and the disadvantage is the difficult differentiation of normal physiologic uptake, the lack of normal anatomical landmarks. PET/CT, the combination of clinical PET and CT imaging in a single unit is introduced recently, and it helps to get more accurate diagnostic interpretation and to improve in evaluating response to therapy, in management of patients with malignant tumors. So, we report the advantages of PET/CT in the diagnosis of oral cancer with review of literatures.
Biochemical Phenomena ; Diagnosis* ; Electrons ; Head ; Head and Neck Neoplasms ; Humans ; Magnetic Resonance Imaging ; Mouth Neoplasms* ; Neck ; Positron-Emission Tomography and Computed Tomography* ; Sensitivity and Specificity

The DNA sequence of a plasmid named pHP489 of Helicobacter pylori strain 489 was determined and analyzed to characterize its replication apparatus. The pHP489 plasmid consisted of 1,222 bp and had an overall G+C content of 33.1%. An ORF was predicted to encode the putative protein of 239 amino acid residues (28 kDa). A putative ribosomal binding site and a potential terminator sequence are located upstream and downstream of the ORF, respectively. However, the consensus sequence for a promoter in upstream of ORF was not found. A potential dna A box was found at 317 nt upstream of a start codon and followed by two-57 bp directed repeats and an inverted repeat. The DNA homology was found in the regions of less than 90 bp among pHPK255, pHPM180, and pHel1 of other H. pylori plasmids and Mycoplasma mycoides plasmids. pHP489K that was produced by pHP489 sequence and C. jejuni derived aph(3')-III, was transformed to various H. pylori isolates and were stably maintained in the H. pylori host without the addition of selective antibiotics for the 30-times subcultues. The plasmic vector, in which the ORF region of pHP489 DNA was deleted, could be transformed into H. pylori. However, the plasmid vector, whose the direct repeats region of pHP489 DNA was deleted, failed to be transformed. The direct repeats region of pHP489 DNA was confirmed to be bound with cytosolic factors of H. pylori. These results showed that the direct repeats region of pHP489 DNA is an essential apparatus by which the plasmid could be replicacted in H. pylori. And pHP489 plasmid was supposed to be replicated by host factors rather than plasmic-encoded factors.
Animals ; Anti-Bacterial Agents ; Base Composition ; Base Sequence ; Binding Sites ; Codon, Initiator ; Consensus Sequence ; Cytosol ; DNA ; Ecthyma, Contagious ; Helicobacter pylori* ; Helicobacter* ; Mycoplasma mycoides ; Plasmids* ; Repetitive Sequences, Nucleic Acid ; Sequence Analysis* ; Terminator Regions, Genetic