A high-affinity peptide substrate for G protein-coupled receptor kinase 2 (GRK2).

We synthesized a previously identified ß-tubulin-derived G protein-coupled receptor kinase 2 (GKR2) peptide (GR-11-1; DEMEFTEAESNMN) and its amino-terminal extension (GR-11-1-N; GEGMDEMEFTEAESNMN) and carboxyl-terminal extension (GR-11-1-C; DEMEFTEAESNMNDLVSEYQ) peptides with the aim of finding a high-affinity peptide substrate for GRK2. GR-11-1-C showed high affinity for GRK2, but very low affinity for GKR5. Its specificity and sensitivity for GKR2 were greater than those of GR-11-1 and GR-11-1-N. These findings should be useful in designing tools for probing GKR2-mediated intracellular signaling pathways, as well as GRK2-specific drugs.

Regulation of cargo-selective endocytosis by dynamin 2 GTPase-activating protein girdin.

In clathrin-mediated endocytosis (CME), specificity and selectivity for cargoes are thought to be tightly regulated by cargo-specific adaptors for distinct cellular functions. Here, we show that the actin-binding protein girdin is a regulator of cargo-selective CME. Girdin interacts with dynamin 2, a GTPase that excises endocytic vesicles from the plasma membrane, and functions as its GTPase-activating protein. Interestingly, girdin depletion leads to the defect in clathrin-coated pit formation in the center of cells. Also, we find that girdin differentially interacts with some cargoes, which competitively prevents girdin from interacting with dynamin 2 and confers the cargo selectivity for CME. Therefore, girdin regulates transferrin and E-cadherin endocytosis in the center of cells and their subsequent polarized intracellular localization, but has no effect on integrin and epidermal growth factor receptor endocytosis that occurs at the cell periphery. Our results reveal that girdin regulates selective CME via a mechanism involving dynamin 2, but not by operating as a cargo-specific adaptor.

The reduction of l-cystine to l-cysteine in the supernatant of A549 cell culture causes imipenem inactivation.

In the course of measuring the intracellular antibacterial activity of antibiotics using a human alveolar epithelial cell line A549, we discovered that the antimicrobial activity of several carbapenems (CPs) decreased in the supernatant of the cells cultured with fetal calf serum (FCS)-free RPMI1640 medium (RPMI). Further investigation revealed A549 culture supernatant inhibited the antibacterial activity of CPs but did not inactivate other types of antibiotics. CE-TOFMS and LC-TOFMS metabolomics analysis of the supernatant revealed the presence of l-cysteine (Cys), which is not an original component in RPMI. Cys is known to hydrolyze and inactivate CPs in a time- and concentration-dependent manner. In this study, the inactivating effects of A549 culture supernatant on the imipenem (IPM) were examined. Antimicrobial activity of 100 µg/mL IPM decreased to 25% with two-fold dilution of A549 supernatant incubated for 3 h. l-Cystine (CS), the Cys oxide, and an original component in RPMI did not inactivate IPM. However, the inactivating effects of A549 supernatant on IPM corresponds with the Cys concentration and depends on the CS content of the culture medium. Addition of FCS to the culture medium decreased the Cys concentration and reduced inactivation of IPM in a dose-dependent manner. Our data suggest that IPM were inactivated by Cys reduced from CS, and this CS-to-Cys conversion must be considered when evaluating the antimicrobial activity of CPs in cell culture. Further studies are needed to understand if the same inactivation occurs around the cells in the human body.

Role of amino acid residues surrounding the phosphorylation site in peptide substrates of G protein-coupled receptor kinase 2 (GRK2).

A series of amino acid substitutions was made in a previously identified ß-tubulin-derived GRK2 substrate peptide (404DEMEFTEAESNMN416) to examine the role of amino acid residues surrounding the phosphorylation site. Anionic amino acid residues surrounding the phosphorylation site played an important role in the affinity for GRK2. Compared to the original peptide, a modified peptide (Ac-EEMEFSEAEANMN-NH2) exhibited markedly higher affinity for GRK2, but very low affinity for GRK5, suggesting that it can be a sensitive and selective peptide for GRK2.

Isolation and antiviral activity of water-soluble Cynomorium songaricum Rupr. polysaccharides.

The plant, Cynomorium songaricum Rupr., is used as a traditional medicine in China and Mongolia. In the present study, two new water-soluble polysaccharides isolated from C. songaricum Rupr. were purified by successive Sephadex G-75 and G-50 column chromatographies and then characterized by high resolution NMR and IR spectroscopies. The molecular weights of two polysaccharides were determined by an aqueous GPC to be [Formula: see text] = 3.7 × 10(4) and 1.0 × 10(4), respectively. In addition, it was found that the polysaccharide with the larger molecular weight was an acidic polysaccharide. It was found that the iodine-starch reaction of both isolated polysaccharides was negative and the methylation analysis gave 2, 4, 6-tri-O-methyl alditol acetate as a main product. NMR and IR measurements and sugar analysis revealed that both polysaccharides had a (1 â†’ 3)-α-d-glucopyranosidic main chain with a small number of branches. After sulfation, the sulfated C. songaricum Rupr. polysaccharides were found to have a potent inhibitory effect on HIV infection of MT-4 cells at a 50% effective concentration of 0.3-0.4 µg/ml, a concentration that has almost the same high activity as standard dextran and curdlan sulfates, EC50 = 0.35 and 0.14 µg/ml, respectively. The 50% cytotoxic concentration was low, CC50>1000 µg/ml. In addition, the interaction between the sulfated polysaccharides and poly-l-lysine as a model protein compound was investigated by a surface plasmon resonance to reveal the anti-HIV mechanism.

Potential new chemotherapy strategy for human ovarian carcinoma with a novel KSP inhibitor.

Among synthetic kinesin spindle protein (KSP) inhibitor compounds, KPYB10602, a six-member lactam-fused carbazole derivative was the most potent in vitro against cell growth of human ovarian cancer, A2780. KPYB10602 caused dose-dependent suppression of tumor growth in vivo. Mitotic arrest due to KPYB10602 was confirmed in vitro, and was characterized by inhibition of securin degradation. Apoptosis after mitotic arrest was associated with an increase in the ratio of pro-apoptotic Bax to anti-apoptotic Bcl-2. Increase of reactive oxygen species (ROS) and caspase pathway were also involved. Furthermore, KPYB10602 caused little neurotoxicity in vivo. Therefore, KPYB10602 could be a promising candidate as an anti-tumor agent with reduced adverse events for treating human ovarian cancer.

The first reported case of central venous catheter-related fungemia caused by Cryptococcus liquefaciens.

We describe a case of central venous catheter-related fungemia caused by Cryptococcus liquefaciens, a non-neoformans and non-gattii Cryptococcus, in a non-HIV patient. A 71-year-old man with diffuse large B-cell lymphoma receiving antineoplastic chemotherapy was febrile approximately 30 weeks after central venous port insertion, and C. liquefaciens was isolated from all three performed blood cultures as well as a central venous catheter tip culture. In vitro antifungal susceptibility tests showed that this yeast isolate was susceptible to low concentrations of amphotericin B, fluconazole, itraconazole and voriconazole yet was resistant to 5-fluorocytosine (MIC: >64 µg/ml), unlike Cryptococcus neoformans. Treatment of the patient with oral and intravenous voriconazole was effective and consistent with the susceptibility tests. Although non-neoformans and non-gattii Cryptococcus spp. are considered non-pathogenic environmental yeast, they may rarely be the causative agents of serious infections in humans, as in the present case.

[Nationwide surveillance of parenteral antibiotics containing meropenem activities against clinically isolated strains in 2012].

The nationwide surveillance of antibacterial susceptibility to meropenem (MEPM) and other parenteral antibiotics against clinical isolates during 2012 in Japan was conducted. A total of 2985 strains including 955 strains of Gram-positive bacteria, 1782 strains of Gram-negative bacteria, and 248 strains of anaerobic bacteria obtained from 31 medical institutions were examined. The results were as follows; 1. MEPM was more active than the other carbapenem antibiotics tested against Gram-negative bacteria, especially against enterobacteriaceae and Haemophilus influenzae. MEPM was also active against most of the species tested in Gram-positive and anaerobic bacteria, except for multi-drug resistant strains including methicillin-resistant Staphylococcus aureus (MRSA). 2. Of all species tested, there were no species, which MIC90 of MEPM was more than 4-fold higher than those in our previous studies in 2009 or 2006. Therefore, the tendency to increase in antimicrobial resistance rates was not observed. 3. MEPM resistance against Pseudomonas aeruginosa was 17.8% (56/315 strains). Compared to our previous results, it was the lowest than that in 2006 and 2009. 4. Carbapenem-resistant Klebsiella pneumoniae, and multi-drug-resistant Acinetobacter species, which emerged in worldwide, were not observed. 5. The proportion of extended-spectrum beta-lactamase (ESBL) strains was 6.2% (59/951 strains) in enterobacteriaceae, which increased compared with that of our previous studies in 2009 or before. Whereas, the proportion of metallo-beta-lactamase strains was 1.6% (5/315 strains) in P. aeruginosa, which was stable. In conclusion, the results from this surveillance suggest that MEPM retains its potent and broad antibacterial activity and therefore is a clinically useful carbapenem for serious infections treatment at present, 17 years passed after available for commercial use in Japan.

Replacement of Arg-386 with Gly in dynamin 1 middle domain reduced GTPase activity and oligomer stability in the absence of lipids.

Dynamin plays an important role in membrane fission during endocytosis, and its middle domain is involved in the formation of functional oligomers. In this study, we found that replacement of Arg-386 with Gly in the middle domain region of dynamin 1 did not affect the intermolecular interactions of dynamin 1 in the presence of phosphatidylserine-liposomes. But, unexpectedly, this variant showed lower guanosine 5'-triphosphatase activity in the absence of phosphatidylserine-liposomes and enhanced monomer formation from oligomers. Our results indicate that GTPase activity in the absence of lipids is important in the dissociation of oligomer complexes, i.e., reduced basal dynamin 1 GTPase activity is associated with instability of dynamin oligomers.

[The New Generation of Particle Therapy Focused on Boron Element (Boron Neutron Capture Therapy; BNCT) -The World's First Approved BNCT Drug].

Boron neutron capture therapy (BNCT) is a type of radiation therapy and a new modality for cancer treatment. The radiation used in BNCT is a very low energy neutron called a "thermal neutron", and unlike other radiation, it has no effect on treating cancer on its own. However, when this neutron collides with boron-10 (10B), which is a stable isotope of boron, fission occurs into a high-energy helium nucleus (α-particle) and a lithium nucleus. Moreover, the effect of this fission reaction is limited to a range of about 10 µm, which corresponds to the approximate size of one cell. Therefore, the basic principle of BNCT is "cell-selective" radiation therapy that only damages cells that have taken up 10B present in the area irradiated with thermal neutrons. For the practical application of BNCT, it is indispensable to generate a boron drug capable of selectively accumulating 10B in cancer cells. We have successfully developed a boron drug for BNCT targeting amino acid transporters. We have obtained manufacturing and marketing approval for the world's first boron drug for BNCT, Steboronine® intravenous drip bag 9000 mg/300 mL (March 25, 2020), for indications of locally unresectable recurrent or advanced unresectable head and neck cancer. This uses Borofalan (10B), which is 10B introduced into l-phenylalanine, as a drug substance. This review describes the progress of drug development and future prospects of boron drugs for BNCT.

[Nationwide surveillance of parenteral antibiotics containing meropenem activities against clinically isolated strains in 2009].

The antibacterial activity of meropenem (MEPM) and other parenteral antibiotics against clinical isolates of 2655 strains including 810 strains of Gram-positive bacteria, 1635 strains of Gram-negative bacteria, and 210 strains of anaerobic bacteria obtained from 30 medical institutions during 2009 was examined. The results were as follows; (1) MEPM was more active than the other carbapenem antibiotics tested against Gram-negative bacteria, especially against enterobacteriaceae and Haemophilus influenzae. MEPM was also active against most of the species tested in Gram-positive and anaerobic bacteria, except for multidrug resistant strains including methicillin-resistant Staphylococcus aureus (MRSA). (2) MEPM maintained potent and stable antibacterial activity against Pseudomonas aeruginosa. The proportion of MEPM-resistant strains to ciprofloxacin-resistant strains or imipenem-resistant strains were 53.1% and 58.0% respectively. (3) The proportion of extended-spectrum beta-lactamase (ESBL) strains was 3.1% (26 strains) in enterobacteriaceae. And the proportion of metallo-beta-lactamase strains was 2.0% (6 strains) in P. aeruginosa. (4) Of all species tested, there were no species except for Bacteroides fragilis group, which MIC90 of MEPM was more than 4-fold higher than those in our previous study. Therefore, there is almost no significant decrease in susceptibility of clinical isolates to meropenem. In conclusion, the results from this surveillance study suggest that MEPM retains its potent and broad antibacterial activity and therefore is a clinically useful carbapenem for serious infections treatment at present, 14 years passed after available for commercial use in Japan.

Suppression of dynamin GTPase activity by sertraline leads to inhibition of dynamin-dependent endocytosis.

Dynamin (Dyn) 1 plays a role in recycling of synaptic vesicles, and thus in nervous system function. We previously showed that sertraline, a selective serotonin reuptake inhibitor (SSRI), is a mixed-type inhibitor of Dyn 1 with respect to both GTP and L-alpha-phosphatidyl-L-serine (PS) in vitro, and we suggested that it may regulate the neurotransmitter transport by modulating synaptic vesicle endocytosis via inhibition of Dyn 1 GTPase. Here, we investigated the effect of sertraline on endocytosis of marker proteins in human neuroblastoma SH-Sy5Y cells and HeLa cells. Sertraline inhibited endocytosis in both cell lines. Western blotting showed that SH-Sy5Y expresses Dyn 1 and Dyn 2, while HeLa expresses only Dyn 2. GTPase assay showed that sertraline inhibited Dyn 2 as well as Dyn 1. Therefore, the effect of sertraline on endocytosis was mediated by Dyn 2, at least in HeLa cells, as well as by Dyn 1 in cell lines that express it. Moreover, the inhibition mechanism of transferrin (Tf) uptake by sertraline differed from that in cells expressing Dyn 1 K44A, a GTP binding-defective variant, and sertraline did not interfere with the interaction between Dyn 1 and PS-liposomes.

Lignin-like activity of Lentinus edodes mycelia extract (LEM).

BACKGROUND: In order to investigate the physiological role of lignin carbohydrate complex present in Lentinus edodes mycelia extract (LEM), this material was separated into seven fractions. MATERIALS AND METHODS: Three high molecular weight fractions (Frs. I-III) were prepared from the water extract by successive ethanol fractionation, dialysis and lyophilization. Four higher molecular weight fractions were prepared from the NaOH extract of the residue, followed by acid precipitation (Fr. IV) and stepwise ethanol precipitation (Frs. V-VII). RESULTS: All fractions showed higher anti-HIV activity than the water extract. Fr. IV showed the highest anti-HIV activity and most potently inhibited the NO production by LPS-stimulated mouse macrophage-like cells (RAW264.7, J774.1). ESR spectroscopy demonstrated that all fractions scavenged superoxide anion and hydroxyl radical. These properties are similar to those displayed by lignin carbohydrate complex, but not by glucans. HPLC analysis demonstrated the presence of lignin precursors, but not that of tannins, flavonoids and their related compounds. CONCLUSION: These results suggest a significant role of lignin-like substances in the expression of several important biological properties displayed by LEM.

Interaction between sulfated 3-O-octadecyl-α-(1→6)-d-glucan and liposomes analyzed by surface plasmon resonance.

To elucidate the role of long alkyl group in sulfated poly- and oligosaccharides on anti-HIV activity, the interaction between sulfated 3-O-octadecyl-(1→6)-α-d-glucopyranan with potent anti-HIV activity and liposomes with diameters of 58 ± 20 nm and 107 ± 28 nm as models of HIV were investigated. SPR measurements of sulfated 3-O-octadecyl-(1→6)-α-d-glucopyranans bearing 2.8 mol% of the octadecyl group and the liposome (diameter = 58 ± 20.0 nm and ζ=0 mV) resulted in an apparent association- ka = 6 × 105 1/M, a dissociation-rate kd = 4 × 10-4 1/s, and a dissociation constants KD = 8 × 10-10 M. The particle size of the sulfated 3-O-octadecyl-(1→6)-α-d-glucopyranan (67 ± 14 nm) measured by DLS increased to 104 ± 25 nm, whereas the ζ potential (-29 mV) was unchanged (-33 mV). For dextran sulfate without an alkyl group, no interaction was observed. These results suggest that the long octadecyl group penetrated into the liposome and sulfated glucopyranan was covered on the liposome to increase the anti-HIV activity. The 107 nm liposome exhibited similar results.

Effect of Fetal Bovine Serum Concentration on Lysophosphatidylcholine-mediated Proliferation and Apoptosis of Human Aortic Smooth Muscle Cells.

Lysophosphatidylcholine (lysoPtdCho) is produced by the phospholipase A2-mediated hydrolysis of phosphatidylcholine and can stimulate proliferation and apoptosis of vascular smooth muscle cells. We examined the influence of fetal bovine serum (FBS) concentration in the culture medium on lysoPtdCho-mediated apoptosis and proliferation of human aortic smooth muscle cells (HASMCs) as well as on the activation of extracellular signal-regulated kinases (ERK)1/2. In the presence of 1% FBS, HASMC viability increased after lysoPtdCho treatment at 1 and 10 µM but decreased at 25 and 50 µM. However, lysoPtdCho increased HASMC viability in a dose-dependent manner in the presence of 10% FBS. The activity of caspase 3/7 in HASMCs was increased by 25 µM lysoPtdCho in the presence of 1% FBS, but not 10% FBS. Furthermore, lysoPtdCho at 1 and 10 µM triggered ERK1/2 phosphorylation in the presence of 1% FBS, but not at 10% FBS. Thus, lysoPtdCho-mediated HASMC apoptosis, proliferation, and ERK1/2 activation are dependent on the concentration of FBS.

Elucidation of anti-HIV mechanism of sulfated cellobiose-polylysine dendrimers.

Three new spherical sulfated cellobiose-polylysine dendrimers of increasing generations bearing negatively charged sulfate groups were prepared by sulfating the corresponding cellobiose-polylysine dendrimers. The first, second, and third-generation derivatives exhibited potent anti-HIV activity with EC50 values of 3.7, 0.6, and 1.5 µg/mL, respectively, in constant to sulfated oligosaccharides with low anti-HIV activity, while the second-generation sulfated dendrimer was the most active. Surface plasmon resonance measurements with poly-l-lysine bearing positively charged amino acids as a model of the HIV surface glycoprotein gp120, indicated that the second-generation dendrimer had the lowest dissociation constant (KD = 1.86 × 10-12 M). Both the particle size and ζ potential increased in the presence of poly-l-lysine. It was proven that the moderate distance between the terminal sulfated cellobiose units in the second-generation dendrimer favored the high anti-HIV activity, owing to the electrostatic interactions developed due to the cluster effect.

Inflammatory cell-specific transgene expression system responding to Ikappa-B kinase beta activation.

BACKGROUND: Control of inflammation is essential for the clinical management of many common human diseases. However, there are few generally applicable strategies to convert an abnormal intracellular signal into a gene expression that leads to normalization of the intracellular environment. Recently, we proposed a novel strategy termed D-RECS (i.e. drug or gene delivery system responding to cellular signals) to convert an intracellular signal to transgene expression. In the present study, we applied this concept to inflammatory cells using Ikappa-B kinase as a signal molecule that triggers the gene expression. METHODS: Candidate cationic substrates of Ikappa-B kinase (IKK)beta were synthesized and their reactivity was investigated. Then, polymers grafted with these peptides were prepared by radical polymerization. Polymer/DNA complexes (polyplexes) were prepared by mixing plasmid DNAs with the polymers. The behaviour of these polyplexes by adding IKKbeta was examined. Furthermore, changes of gene expression were evaluated after the microinjection of polyplex into living cells under conditions of nuclear factor (NF)-kappaB activation. RESULTS: Synthetic peptides with additional lysine residues were well phosphorylated by IKKbeta. Both the polymer and the polyplex were also phosphorylated by IKKbeta. The results of gel shift assay showed that the polyplex was disintegrated and free DNA was released in the presence of IKKbeta. The polyplex comprising-green fluorescent protein plasmid DNA and the polymer expressed the transgene in living cells exposed to a pro-inflammatory stimulus. CONCLUSIONS: Our concept of cell-specific gene expression was demonstrated to work in inflammatory cells. This method may provide a unique strategy for gene therapy exclusively in inflammatory cells.

Selective antibacterial and apoptosis-modulating activities of mastic.

Mastic is a resinous exudate obtained from the stem and the main leaves of Pistacia lentiscus. We have reported the antiplaque effect of mastic-containing chewing gum on the oral cavity. We hypothesize that mastic may be a multifunctional food which has some beneficial pharmaceutical properties. The aim of this study was to assess the biological activity of solid and liquid types of mastic by cytotoxicity against fibroblasts, radical-scavenging activities and inhibitory effect on cell death of oral polymorphonuclear leukocytes (OPMNs). Mastic showed selective antibacterial action against Porphyromonas gingivalis and Prevotella melaninogenica, but no anti-HIV activity. Among a total of thirteen human cell types, promyelocytic leukemia HL-60 was the most sensitive to the cytotoxicity of mastic, followed by myeloblastic leukemia (ML-1, KG-1), erythroleukemia (K-562), oral squamous cell carcinoma (HSC-2, HSC-3, HSC-4), hepatocellular carcinoma (HepG2), glioblastoma (T98G, U87MG) and normal oral cells (gingival fibroblast, pulp cell, periodontal ligament fibroblast, most resistant). Mastic did not induce the differentiation of myelogenous leukemic cells into maturing cells with higher nitroblue tetrazolium-reducing activity, but induced apoptotic cell death, characterized by internucleosomal DNA fragmentation, caspase-3 activation and a decline in the intracellular concentration of putrescine. The cytotoxicity of mastic against leukemic cells did not diminish during its storage. On the other hand, mastic inhibited the spontaneous apoptosis of OPMNs. Mastic showed hydroxyl radical-scavenging activity. The selective antibacterial and apoptosis-modulating activity of mastic suggests its possible beneficial effects on oral health.

Injectable Polypeptide Hydrogel Depot System for Assessment of the Immune Response-Inducing Efficacy of Sustained Antigen Release Alone.

Vaccines typically contain an antigen, delivery system (vehicle), and adjuvant, all of which contribute to inducing a potent immune response. Consequently, design of new vaccines is difficult, because the contributions and interactions of these components are difficult to distinguish. Here, it is aimed to develop an easy-to-use, non-immunogenic, injectable depot system for sustained antigen release that will be suitable for assessing the efficacy of prolonged antigen exposure per se for inducing an immune response. This should mimic real-life infections. Recombinant elastin-like polypeptides with periodic cysteine residues (cELPs) are selected, which reportedly show little or no immunogenicity, as carriers and tetanus toxoid (Ttd) as an antigen. After subcutaneous injection of the mixture, cELP rapidly forms a disulfide cross-linked hydrogel in situ, within which Ttd is physically incorporated, affording a biodegradable antigen depot. A series of Ttd-containing hydrogels is examined. A single injection induces high levels of tetanus antibody with high avidity for at least 20 weeks in mice. The chain length of cELP proves critical, whereas differences in hydrophobicity has little effect, although hydrophilic cELPs are more rapidly biodegraded. This system's ability to distinguish the contribution of sustained antigen release to antibody induction should be helpful for rational design of next-generation vaccines.

Analysis of interaction between sulfated polysaccharides and HIV oligopeptides by surface plasmon resonance.

This study aims to quantitatively investigate the interaction between sulfated polysaccharides with potent anti-HIV activity, dextran and curdlan sulfates with negatively charged sulfate groups, and poly-L-lysine as a model protein and oligopeptides from a HIV surface glycoprotein gp120 with positively charged amino acids using surface plasmon resonance (SPR) and dynamic light scattering (DLS) to elucidate the anti-HIV mechanism of sulfated polysaccharides. The apparent association- (ka) and dissociation rate (kd) constants of dextran and curdlan sulfates against poly-L-lysine were ka = 6.92 × 104-2.17 × 106 1/Ms and kd = 4.29 × 10-5-2.22 × 10-4 1/s; these kinetic constants were dependent on the molecular weights and degree of sulfation of sulfated polysaccharides. For interaction, the three oligopeptides from the HIV gp120 were peptide A 297TRPNNNTRKRIRIQRGPGRA316 with several lysine (K) and arginine (R) in the V3 loop region, peptide B 493PLGVAPTKAKRRVVQREKR511 with several K and R in the C-terminus region, and oligopeptide C 362KQSSGGDPEIVTHSFNCGG380 with few basic amino acids in the CD4 binding domain. Sulfated polysaccharides exhibited strong interaction against oligopeptides A and B, (ka = 5.48 × 104-2.96 × 106 1/Ms. and kd = 1.74 × 10-4-6.24 × 10-3 1/s), no interaction was noted against oligopeptide C. Moreover, the particle size and zeta potential by DLS indicated the interaction between sulfated polysaccharides and oligopeptides A and B, suggesting the anti-HIV mechanism of sulfated polysaccharides to be the electrostatic interaction of negatively charged sulfated polysaccharides and HIV at the positively charged amino acid regions.