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At least 19 recordsLinked to original sources
PubMed1991

Altered distribution of basic fibroblast growth factor in diabetic retinopathy.

Basic fibroblast growth factor (FGF) is a potent endothelial cell mitogen that has been proposed to play a role in proliferative diabetic retinopathy and other neovascular processes. Our understanding of the in vivo role of basic FGF in the pathogenesis of these disorders is limited. We studied the immunolocalization of basic FGF in 16 clinical cases of diabetic retinopathy to determine whether the normal retinal distribution of basic FGF changed during the development of diabetic retinopathy and correlated with the onset of retinal neovascularization. By using monoclonal and affinity-purified polyclonal antibodies against basic FGF and heparan sulfate proteoglycan (HSPG), we found that basic FGF colocalized with HSPG to vascular basement membranes. As the basement membranes thickened during the progression of diabetic retinopathy, the intraretinal stores of immunoreactive basic FGF and HSPG expanded. With the development of neovascularization, the colocalization of basic FGF and HSPG changed; HSPG localized to basement membranes, while basic FGF localized intracellularly, with only minimal basement membrane immunoreactivity. Incubations of the neovascular fronds with exogenous basic FGF demonstrated multiple HSPG glycosaminoglycan-binding sites for basic FGF, indicating that basic FGF had not been released from the matrix of neovascular fronds by heparitanase digestion.

Antibodies, Monoclonal↗
PubMed1998

Characterization of enzymatic pectin digests by matrix-assisted laser desorption/ionization mass spectrometry.

The use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for the characterization of partially methyl-esterified enzymatic pectin digests is described. The sensitivities of several matrices, positive and negative ion modes and desalting techniques for these acidic oligosaccharides were compared. The most favorable results were obtained with a thin-layer preparation of a mixture of 2,4,6-trihydroxyacetophenone and nitrocellulose in the negative ion mode. Results are presented demonstrating the sensitive characterization of separated and unseparated high-ester pectin digests obtained after complete digestion using Aspergillus niger pectin lyase and the analysis of digests after chemical modification. In the case of unseparated digests, the analysis of methylation patterns is demonstrated. Oligomers with a degree of polymerization up to 40 were detected after enrichment of large oligomers by propan-2-ol precipitation.

1-Propanol↗
PubMed1997

Role of heparin-binding EGF-related peptides in proliferation and apoptosis of activated ras-stimulated intestinal epithelial cells.

The ras mutation is a common and critical step in carcinogenesis. Autocrine growth factors are also known to play an important role in cancer cell growth and transformation. However, the contribution of autocrine growth factors in regulation of proliferation and apoptosis of activated ras-stimulated intestinal epithelium is not fully understood. Therefore, we constructed activated ras-transfected intestinal epithelial cell clones (IEC-ras) to examine the role of epidermal growth factor (EGF)-related peptides in the behavior of IEC-ras. Overexpression of EGF family growth factors (transforming growth factor alpha, heparin-binding EGF-like growth factor, amphiregulin and betacellulin) and stronger phosphorylation of the EGF receptor was observed in IEC-ras compared with control cells. IEC-ras proliferated more rapidly than control cells, and a specific EGF receptor kinase inhibitor, AG 1478, abolished the increased proliferation of IEC-ras. Heparitinase and chlorate also prevented increased proliferation of IEC-ras. Additionally, IEC-ras expressed more bcl-2 and was more resistant to apoptosis induction by UV radiation and mitomycin C. AG 1478 suppressed bcl-2 expression and inhibited resistance to apoptosis of IEC-ras. Heparitinase and chlorate had effects similar to those of AG 1478. Our data indicate that heparin-binding EGF family growth factors play an important role in both increased proliferation and resistance to apoptosis of ras-stimulated intestinal epithelial cells.

Amphiregulin↗
PubMed1999

Characterization of the N-linked glycosylation site of recombinant pectate lyase.

Recombinant pectate lyase from Aspergillus niger was overexpressed in Aspergillus nidulans. The two recombinant proteins produced differed in molecular mass by 1200 Da, which suggested that the larger molecular weight protein was glycosylated. The deduced amino acid sequence was searched for potential N-linked glycosylation sites, and one potential site was identified at residue 64. The proteins were analyzed for their ability to bind various lectins as an assay for the presence of carbohydrates. The proteins were then digested with trypsin to facilitate the isolation of the potential glycosylation site. The resulting digestion products were subsequently analyzed by liquid chromatography/mass spectrometry using in-source collision induced dissociation to detect glycopeptides. Once the glycopeptide had been identified, treatment with an endoglycosidase both verified the location of glycosylation and identified the mass of the glycan. The Complex Carbohydrate Structural Database was searched for possible N-linked structures with the same mass, and the suggested primary sequence was confirmed by an exoglycosidase digestion. The data demonstrated that the larger recombinant protein contained a high mannose N-linked structure (Man(5)GlcNAc(2)) attached to N-64, while this site was not occupied in the smaller protein.

Aspergillus nidulans↗
PubMed1999

p200, a collagen secreted by Schwann cells, is expressed in developing nerves and in adult nerves following axotomy.

Previously we reported that cultured rat Schwann cells secrete p200, a collagen-like heparin-binding adhesive glycoprotein with a restricted pattern of expression. Here we report that p200 is secreted as a stable trimer, but only after treatment of Schwann cells with ascorbic acid, and was deposited in the fibrillar extracellular matrix. Heparin and heparitinase treatment inhibited incorporation of p200 into extracellular matrix, suggesting the involvement of Schwann cell heparan sulfate proteoglycans in this process. Pepsin digestion revealed that p200 secreted by ascorbate-treated cells contains a collagenous domain of approximately 140 kDa. Immunofluorescent staining of rat embryos at different ages showed that p200 first appeared between embryonic days 15 and 18, and was confined to peripheral nerves. Staining of adult peripheral nerve was negative, but p200 expression was induced in adult sciatic nerve following nerve transection. These data suggest that p200 carries out unique functions during peripheral nerve development and regeneration and that its expression by Schwann cells is regulated by axon-Schwann cell interaction.

Aging↗
PubMed1996

Visualization of several binding sites for basic fibroblast growth factor (FGF-2) on fibroblasts by photoaffinity labeling: evidence for intracellular complexes.

The internalization of basic fibroblast growth factor (FGF-2) was studied in Chinese hamster lung fibroblasts (CCL39). Recombinant FGF-2 was derivatized with a photoactivable agent, N-hydroxysuccinimidyl-4-azidobenzoate (HSAB), iodinated, and used to visualize intracellular FGF-2-affinity-labeled molecules after internalization at 37 degrees C. Iodinated HSAB-FGF-2 maintained the properties of natural FGF-2 such as affinity for heparin, binding to Bek and Fig receptors, interaction with high- and low-affinity binding sites, and reinitiating of DNA synthesis in CCL39 cells. Affinity-labeling experiments at 4 degrees C with 125I-HSAB-FGF-2 led to the detection of several FGF-cell surface complexes with apparent molecular mass of 80, 100, 125, 150, 170-180, 220, 260, and about 320 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), whereas two specific bands at 80 and 130-160 kDa were obtained using the homobifunctional cross-linking reagent, disuccinimidyl suberate. When the cells, preincubated with 125I-HSAB-FGF-2 at 4 degrees C and then washed, were shifted to 37 degrees C, irradiation of the internalized labeled FGF-2 led to detection of a similar but fainted profile with one major specific band at 80 kDa. Heparitinase II treatment of the cells reduced binding of 125I-HSAB-FGF-2 to its cell surface sites by 80% and internalization by 55%, indicating the involvement of heparan sulfate proteoglycans in these processes. Among the heparitinase-sensitive bands was the 80-kDa complex.

Affinity Labels↗
PubMed1997

Interaction between Alzheimer's disease beta A4 precursor protein (APP) and the extracellular matrix: evidence for the participation of heparan sulfate proteoglycans.

The interaction between the Alzheimer amyloid precursor protein (APP) and an intact extracellular matrix (ECM), matrigel, obtained from Engelbreth-Holm-Swarm tumors was evaluated. Based on quantitative analyses of the binding data obtained from solid phase binding assays, two binding sites on the ECM were identified for [125I]-APP (with apparent Kd1 of 1.0 x 10(-11) M and Kd2 of 1.6 x 10(-9) M respectively). Over 70% of [125I]-APP was displaced by heparin and N-desulfated heparin but not by chondroitin sulfate. Pretreatment of matrigel with heparitinase decreased the binding of [125I]-APP by 80%. beta-amyloid peptides (residues 1-40, 1-28, and 1-16) containing a heparin binding domain also displaced 80% of bound [125I]-APP, which was totally displaced by intact APP. The binding of [125I]-APP to matrigel increased by 210% with a decrease in the pH. These observations suggest that [125I]-APP interacts mainly with heparan sulfate proteoglycan present in the ECM. The binding of [125I]-APP to individual ECM components was also analyzed. [125I]-APP was found to bind laminin and collagen type IV but not fibronectin. However, when these ECM constituents were combined, the extent of APP-binding decreased significantly, to levels comparable to those obtained with intact matrigel, suggesting that multiple interactions may occur between ECM constituents and [125I]-APP. The results are discussed in terms of APP function and amyloidogenesis.

Alzheimer Disease↗
PubMed1997

Extracellular matrix heparan sulfate modulates endothelial cell susceptibility to Staphylococcus aureus.

The ability of extracellular matrix heparan sulfate to alter the susceptibility of human endothelial cells to S. aureus was investigated. Endothelial cells grown on extracellular matrix synthesized by S. aureus-infected endothelial cells were more susceptible to subsequent staphylococcal infection than endothelial cells grown on the extracellular matrix synthesized by untreated endothelial cells. Endothelial cells were more susceptible to S. aureus infection when 1) grown on heparitinase-treated extracellular matrix that removed heparan sulfate chains, 2) grown on extracellular matrix produced by chlorate-treated endothelial cells that reduced sulfation in the matrix heparan sulfate proteoglycans, 3) grown on heparan sulfate purified from extracellular matrix elaborated by infected endothelial cells, and 4) endothelial cells were chlorate-treated and therefore expressed desulfated cellular heparan sulfate proteoglycans. Extracellular matrix produced by S. aureus-infected endothelial cells contained heparan sulfate proteoglycans with reduced sulfation. The altered extracellular matrix with reduced sulfated heparan sulfate proteoglycans signalled the uninfected endothelial cells to produce under sulfated cellular heparan sulfate proteoglycans that increased S. aureus adherence to the endothelial cells.

Bacterial Adhesion↗
PubMed1999

Thymic epithelial cells synthesize a heparan sulfate with a highly sulfated region.

Epithelial cells are important components of the thymus microenvironment and are involved in thymocyte differentiation. The production and secretion of sulfated glycosaminoglycans by these cells grown in culture were investigated using labeling with radioactive 35S-Na2SO4 and 3H-glucosamine. The major glycosaminoglycans synthesized by these cells are heparan sulfate and hyaluronic acid. The structure of the heparan sulfate was investigated by the pattern of degradation products formed by deaminative cleavage with nitrous acid. The ratio 35S-sulfate/ H-glucosamine is high in the segments of the heparan sulfate released during the deaminative cleavage with nitrous acid but low in the resistant portion of the molecule. Thus, the heparan sulfate synthesized by the thymic epithelial cells contains a highly sulfated region. Digestion with heparitinase reveals that this highly sulfated region is a heparin-like segment of the molecule. The heparan sulfate is rapidly incorporated into the cell surface but its secretion to the extracellular medium requires a longer incubation period. Finally, heparin was used to mimic the possible effect of this heparan sulfate with a highly sulfated region, as ascertained by its ability to modulate thymocyte adhesion to thymic epithelial cells. Since heparin actually enhanced thymocyte adhesion, it is suggested that the heparan sulfate described herein, secreted by the thymic epithelium, may play a role upon intrathymic heterotypic cellular interactions.

Animals↗
PubMed2000

Characterization of factors regulating lamina-specific growth of thalamocortical axons.

During development, most thalamocortical axons extend through the deep layers to terminate in layer 4 of neocortex. To elucidate the molecular mechanisms that underlie the formation of layer-specific thalamocortical projections, axon outgrowth from embryonic rat thalamus onto postnatal neocortical slices which had been fixed chemically was used as an experimental model system. When the thalamic explant was juxtaposed to the lateral edge of fixed cortical slice, thalamic axons extended farther in the deep layers than the upper layers. Correspondingly, thalamic axons entering from the ventricular side extended farther than those from the pial side. In contrast, axons from cortical explants cultured next to fixed cortical slices tended to grow nearly as well in the upper as in the deep layers. Biochemical aspects of lamina-specific thalamic axon growth were studied by applying several enzymatic treatments to the cortical slices prior to culturing. Phosphatidylinositol phospholipase C treatment increased elongation of thalamic axons in the upper layers without influencing growth in the deep layers. Neither chondroitinase, heparitinase, nor neuraminidase treatment influenced the overall projection pattern, although neuraminidase slightly decreased axonal elongation in the deep layers. These findings suggest that glycosylphosphatidylinositol-linked molecules in the cortex may contribute to the laminar specificity of thalamocortical projections by suppressing thalamic axon growth in the upper cortical layers.

Animals↗
PubMed2000

Benign hyperplasia of the human prostate is associated with tissue enrichment in chondroitin sulphate of wide size distribution.

BACKGROUND: Benign prostatic hyperplasia (BPH) involves qualitative and quantitative alterations in extracellular matrix (ECM) components affecting stromal-epithelial interactions. Glycosaminoglycans (GAGs) are polysaccharide components of the ECM whose role in the development of BPH is under investigation. METHODS: GAGs were extracted from human prostates of normal and BPH origin and were subsequently fractionated through DEAE-sephacel anion exchange chromatography. The isolated GAG fractions were identified through electrophoresis on cellulose acetate membranes and treatment with GAG-degrading enzymes of known specificity. Their size distribution was determined through gradient polyacrylamide gel electrophoresis. RESULTS: Isolated prostatic GAGs included hyaluronic acid (HA), heparan sulphate (HS), and a mixture of dermatan sulphate (DS) and chondroitin sulphate (CS). The CS/DS ratio was significantly higher in hyperplastic as compared to normal prostates. A difference was also observed with respect to the apparent molecular mass of the DS-CS mixture, which reflects the CS enrichment in BPH. GAGs isolated from hyperplastic prostates were more diverse in size as compared to the corresponding glycans from normal prostates. CONCLUSIONS: The apparent increase in CS and decrease in DS content in prostates of patients with BPH is in good agreement with the pathological manifestation of increased cell proliferation in hyperplastic prostate tissue, since these glycan molecules have been reported to increase and decrease cell proliferation, respectively. Identification of the responsible enzymes involved in the homeostasis of CS and DS may provide alternative targets for pharmacological intervention.

Adult↗
PubMed2000

cDNA cloning of bovine midkine and production of the recombinant protein, which affects in vitro maturation of bovine oocytes.

In the present study, we cloned bovine midkine (bMK) cDNA by RT- and RACE-PCR, and determined its nucleotide sequence. The nucleotide and deduced amino acid sequences of bMK showed a high degree of homology to those of mouse and human MK. Moreover, a large amount of recombinant bMK (rbMK) was produced using a baculovirus expression system and the protein was purified to homogeneity by heparin affinity chromatography. To examine whether treatment with rbMK during in vitro maturation (IVM) of bovine cumulus-enclosed oocytes affects their nuclear maturation and postfertilization development to the blastocyst stage, bovine cumulus-enclosed oocytes obtained from slaughterhouse-derived ovaries were cultured for 24 hr in IVM medium without (control) or with various concentrations (50-400 ng/ml) of rbMK, followed by in vitro fertilization (IVF) and culture. Although rbMK treatment during IVM did not affect the rates of nuclear maturation and postfertilization cleavage of oocytes, rbMK at all experimental concentrations significantly (P < 0.05) increased the blastocyst yields per tested and per cleaved oocyte compared to the control. Next, it was examined whether heparitinase (HTN) treatment of cumulus-enclosed oocytes would affect the enhancing activity of rbMK during IVM on the developmental competence of oocyte after IVF. The enhancing activity of rbMK was completely suppressed by HTN (1.0 mU/ml) treatment. These results indicate that the presence of rbMK during IVM of bovine cumulus-enclosed oocytes can enhance their developmental competence to the blastocyst stage after IVF and suggest that heparan sulfate chains on the cell surface of cumulus cells and/or oocytes are required for bMK to exert its effect.

Amino Acid Sequence↗
PubMed2001

Heparan sulfate, heparin, and heparinase activity detection on polyacrylamide gel electrophoresis using the fluorochrome tris(2,2'-bipyridine) ruthenium (II).

The paper shows the ability of the fluorochrome tris(2,2'-bipyridine) ruthenium (II) (Rubipy) to detect heparan sulfate, heparin, and heparinase activity of M3 murine mammary adenocarcinoma cells as well as bacterial heparinases I, II, and III in native polyacrylamide gel electrophoresis (PAGE). The technique is based on the electrophoretic mobility of high molecular weight heparins and subsequent staining with Rubipy (50 micrograms/mL). The minimum content of heparin detected by fluorescence in a UV transilluminator was 25-50 ng. The number of Rubipy molecules bound to heparin, determined in relationship to the number of disaccharide units (DU), showed that two to six heparin disaccharide units are bound by each fluorochrome molecule. Scatchard plot analysis showed one Rubipy-binding site (Kd = (8.56 +/- 2.97) x 10(-5) M). Heparinase activity was determined by densitometric analysis of the fluorescence intensity of the heparin-containing band of the gel. While heparinase I (EC 4.2.2.7.) degraded heparin and, to a lower degree, partially N-desulfated N-acetylated heparin (N-des N-Ac), heparinase II (no EC number) could efficiently degrade heparan sulfate (HS) and partially N-des N-Ac heparin. Finally, heparinase III (EC 4.2.2.8.) degraded HS almost exclusively. Only heparin and N-des N-Ac heparin were substrates for M3 tumor cell heparinases. We describe a qualitative, sensitive and simple method to detect heparinase activity and determine its substrate specificity using Rubipy fluorescence with heparin and heparan sulfate in multiple biological samples tested in parallel.

2,2'-Dipyridyl↗
PubMed1984

Effect of heparin on platelet aggregation.

The effect of heparin on platelet aggregation was systematically examined on platelets in plasma (PRP), as well as on gel-filtered, washed, and formaldehyde-fixed platelets. Results indicate that, although heparin causes a mild potentiation of platelet aggregation in the PRP systems, a significant inhibitory activity is observed when heparin is added to isolated platelets. This inhibitory activity appears to be specific and not related to the impurities in the heparin preparations, as heparinase, as well as protamine, effectively neutralizes the heparin-mediated inhibitory activity on platelet aggregation. Although heparin-mediated inhibitory activity can be demonstrated in the presence of a number of different agonists (ADP, arachidonic acid, thrombin, Ionophore A23187, epinephrine, and ristocetin), the most pronounced inhibition is seen in the presence of ristocetin. Further studies show that heparin enhances thromboxane generation in isolated platelets. Platelets pretreated with heparin, however, fail to respond to preformed thromboxane. These findings suggest that, in addition to the potentiation of thromboxane production in platelets, heparin may also attribute some change(s) to the platelet(s)/platelet membrane, which interferes with their ability to respond to the agonists of platelet aggregation. This antiaggregatory activity of heparin was found to be inhibited by a factor(s) present in plasma but not in serum.

Blood Coagulation↗
PubMed1985

Heparin-mediated neutralization of platelet antiaggregatory activity of prostacyclin (PGI2): studies on mechanism.

Prostacyclin (PGI2) is a well-known potent inhibitor of platelet aggregation. Its role has been implicated in physiological and pathological states of hemostasis. Heparin blocks the prostacyclin-mediated antiaggregatory activity on platelets. Prior treatment of heparin with heparinase as well as with protamine destroyed heparin's ability to neutralize PGI2. Studies on the mechanism of heparin blocking of PGI2 activity suggested that heparin interacted directly with PGI2, as shown by the loss of PGI2 mobility on thin layer chromatography concomitant with the loss of PGI2-mediated inhibition of platelet aggregation. PGI2 in this combination with heparin, nevertheless, retained its time-dependent ability to be hydrolyzed to 6-keto-PGF1 alpha. Findings of these studies may have implications in thrombosis and hemostasis, particularly in heparin-mediated abnormalities of circulating platelets.

Chromatography, Thin Layer↗
PubMed2006

Inhibitory effects of triterpenes and flavonoids on the enzymatic activity of hyaluronic acid-splitting enzymes.

The effect of triterpenes and flavonoids on the activity of several hyaluronic acid-splitting enzymes was investigated. Studies showed that the inhibitory effect of the triterpenes glycyrrhizin and glycyrrhetinic acid is dependent on the source of hyaluronate lyase. Hyaluronate lyase from Streptococcus agalactiae (Hyal B) and recombinant hyaluronate lyase from Streptococcus agalactiae (rHyal B) demonstrated strongest inhibition. In contrast, hyaluronate lyases from Streptomyces hyalurolyticus (Hyal S), Streptococcus equisimilis (Hyal C) and hyaluronidase from bovine testis (Dase) showed only reduced inhibition action. A non-competitive dead end inhibition with Ki=3.1+/-1.8x10(-6) mol/mL and Kii=6.7+/-2.4x10(-6) mol/mL was found for glycyrrhizin on recombinant hyaluronate lyase from Streptococcus agalactiae. The inhibitory effect of flavonoids on Hyal B, rHyal B and Dase was determined depending on the number of hydroxyl groups and side chain substituents in the molecule. Flavonoids with many hydroxyl groups inhibited hyaluronate lyase stronger than those with only a few. Native hyaluronate lyase (Hyal B) showed a more extensive inhibition than the recombinant protein (rHyal B). Accordingly, the inhibition by triterpenes and flavonoids is presumably specific for each hyaluronic acid (HA)-splitting enzyme.

Animals↗
PubMed1990

Randomness in the heparin polymer: computer simulations of alternative action patterns of heparin lyase.

Heparin is a mixture of linear polysaccharides of undetermined sequence. Both biosynthetic data and computer simulation studies have established that each heparin polymer chain is comprised of oligosaccharides of defined sequence, representing ordered domains. One such ordered domian is a pentasaccharide corresponding to heparin's antithrombin III binding site. Previous computer simulation studies, performed under the assumption that heparin lyase (heparinase, EC 4.2.2.7), has a random endolytic action pattern, suggested that certain of these ordered oligosaccharide domains may themselves be nonrandomly arranged in the heparin polymer. The present work presents computer simulations of alternative action patterns for heparin lyase while assuming a random distribution of these oligosaccharide units within the heparin polymer. We consider action patterns that are determined solely by the primary structure of the substrate molecules. Results of the simulations are compared to (1) the experimental measurements of product chains formed throughout the reaction and (2) the change in weight average molecular weight Mw as a function of reaction completion as determined by absorbance at 232 nm. From the simulation of 60 action patterns for heparin lyase, we infer that one of the following statements concerning heparin and heparin lyase is true: (1) Heparin is a random arrangement of a small number of structurally defined oligosaccharide units. Heparin lyase changes its action pattern during the depolymerization of heparin (perhaps influenced by the secondary structure of substrate). (2) Heparin contain clusters of oligosaccharide sequences that are present in low concentrations (overall) in the polymer. Heparin lyase has a specificity for cleaving glycosidic linkages either exolytically at the nonreducing terminus of a chain or (endolytically) at the reducing side of these rare oligosaccharide sequence.

Carbohydrate Conformation↗
PubMed2004

Preparation of single cells from aggregated Taxus suspension cultures for population analysis.

A method for the isolation of single plant cells from Taxus suspension cultures has been developed for the analysis of single cells via rapid throughput techniques such as flow cytometry. Several cell wall specific enzymes, such as pectinase, pectolyase Y-23, macerozyme, Driselase(R), and cellulase were tested for efficacy in producing single cell suspensions. The method was optimized for single cell yield, viability, time, and representivity of aggregated cell cultures. The best combination for single cell isolation was found to be 0.5% (w/v) pectolyase Y-23 and 0.04% (w/v) cellulase. High viability (>95%) and high yields of single cell aggregates (>90%) were obtained following 4 hours of digestion for four separate Taxus cell lines. In addition, methyl jasmonate elicitation (200 microM) was found to have no effect on three of the four tested Taxus lines. Isolated single cells were statistically similar to untreated cell cultures for peroxidase activity (model cell wall protein) and paclitaxel content (secondary metabolite produced in Taxus cell cultures). In comparison, protoplasts showed marked changes in both peroxidase activity and paclitaxel content as compared to untreated cultures. The use of flow cytometry was demonstrated with isolated cells that were found to have > 99% viability upon staining with fluorescein diacetate. The development of a method for the isolation of single plant cells will allow the study of population dynamics and culture variability on a single cell level for the development of population models of plant cell cultures and secondary metabolism.

Cell Aggregation↗