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1.
I. A. Kostanyan S. S. Zhokhov M. V. Astapova S. M. Dranitsyna A. P. Bogachuk L. K. Baidakova I. L. Rodionov I. I. Baskin O. N. Golubeva J. Tombran-Tink V. M. Lipkin 《Russian Journal of Bioorganic Chemistry》2000,26(9):505-511
It was shown that the full-size neurotrophic factor from pigment epithelium (PEDF) induces the cell differentiation of the
human promyelocyte leukemia cell line HL-60. A structural analysis of PEDF revealed in itsC-terminal region a six-membered peptide fragment PEDF-(352-357) (PEDF-6) whose sequence is highly homologous to the 41–46
fragment of the active site of the human leukocyte differentiation factor HLDF (HLDF-6). The biological effect of PEDF and
synthetic peptides PEDF-6 and HLDF-6 on the HL-60 cells and the early gastrula ectoderm ofXenopus laevis embryos was studied. On the basis of the structural and functional homologies of HLDF, PEDF, and their homologous peptides
and the computer models of the spatial structures of the full-size PEDF and the PEDF with theC-terminal fragment split off tby the cleavage of the Leu380-Thr381 bond in the serpin loop, a hypothesis on the functional role of the serpin loop in PEDF was put forward. 相似文献
2.
Dranitsyna SM Kostanian IA Andreeva SG Astapova MV Babichenko II Baeva OV Bogachuk AP Molotkovskaia IM Rodionov IL Smirnova EV Lipkin VM 《Bioorganicheskaia khimiia》2000,26(5):340-351
A structural homology between the endogenous differentiation factor of the HL-60 cell line of promyelocyte leukemia (HLDF) and several DNA/RNA-binding and DNA/RNA-hydrolyzing proteins was revealed, and expression of the hldf gene in prokaryotic systems was studied. On the basis of these experiments, the amino acid sequence of an 8-membered fragment of HLDF with potential nuclease activity was identified. The synthetic octapeptide RRWHRLKE was shown to be capable of the cleavage of RNA, linear DNA from phage lambda, and all forms of plasmid DNA. We established that treatment of the HL-60 cell culture with this peptide (10(-6) M) results in an increase in the number of apoptotic cells and suggested that HLDF is involved in processes of apoptosis. 相似文献
3.
I. A. Kostanyan M. V. Astapova E. V. Navolotskaya T. N. Lepikhova S. M. Dranitsyna G. B. Telegin I. L. Rodionov L. K. Baidakova Yu. A. Zolotarev I. M. Molotkovskaya V. M. Lipkin 《Russian Journal of Bioorganic Chemistry》2000,26(7):450-456
Six-membered peptide fragment TGENHR (HLDF-6) was identified in the HL-60 cell culture of human promyelocyte leukemia treated
with retinoic acid when studying the differentiation factor HLDF of this cell line. HLDF-6 retains the ability of the full-size
factor to induce the differentiation and arrest the proliferation of the starting HL-60 cells. It was shown that the synthetic
peptide HLDF-6 has no specific receptors on the surface of the HL-60 cells but can affect the binding of interleukin IL-1β,
a cytokine involved in proliferation, to the cell surface. It was found on a model of transplantable NSO myeloma that HLDF-6
has an antitumor activity. 相似文献
4.
Succinyl acetone (SA) was initially identified in the urine of patients with tyrosinemia type I, an autosomally recessive
inherited disease. SA has been used to downregulate the activity of myeloperoxidase (MPO) through its specific inhibition
of heme biosynthesis and to investigate the biological properties of MPO in the human myeloid leukemic (HL-60) cell line.
The goal of this study is to evaluate the mutagenic potential of SA by determining the frequencies of somatic mutations in
the hypoxanthine-guanine phosphoribosyl transferase (HPRT) reporter gene in HL-60 cells following treatment with the chemical.
Treatments of HL-60 cells with 500 μmol/L SA for 72 h, a condition generally used to inhibit the MPO activity, resulted in
a significantly increased HPRT mutant frequency (HPRT-Mf), compared with the control of untreated cells (47.25 × 10-6 versus 7.5 × 10-6, respectively, p <0.01). Treatment of the cells with lower doses of SA also led to an increase in HPRT-Mf but this was significant only with
200 μmol/L (28.67 × 10-6, p<0.05) and not with doses lower than 100 μmol/L (p0.05), compared with the control of untreated cells (7.5 × 10-6). These data show a dose–response increase in HPRT-Mf in HL-60 cells treated with SA, suggesting that this chemical causes
mutations in the HPRT locus in these cells either directly or indirectly through its inhibition of the MPO activity. 相似文献
5.
Although arsenic trioxide (ATO) has been the subject of toxicological research, in vitro cytotoxicity and genotoxicity studies
using relevant cell models and uniform methodology are not well elucidated. Hence, the aim of the present study was to evaluate
the cytotoxicity and genotoxicity induced by ATO in a human leukemia (HL-60) cell line using the MTT [3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium
bromide] and alkaline single cell gel electrophoresis (Comet) assays, respectively. HL-60 cells were treated with different
doses of ATO for 24 h prior to cytogenetic assessment. Data obtained from the MTT assay indicated that ATO significantly (P < 0.05) reduced the viability of HL-60 cells in a dose-dependent manner, showing a LD50 value of 6.4 ± 0.6 μg/mL. Data generated from the comet assay also indicated a significant dose-dependent increase in DNA
damage in HL-60 cells associated with ATO exposure. We observed a significant increase (P < 0.05) in comet tail-length, tail arm and tail moment, as well as in percentages of DNA cleavage at all doses tested, showing
an evidence of ATO-induced genotoxic damage in HL-60 cells. This study confirms that the comet assay is a sensitive and effective
method to detect DNA damage caused by heavy metals like arsenic. Taken together, our findings suggest that ATO exposure significantly
(P < 0.05) reduces cellular viability and induces DNA damage in HL-60 cells as assessed by MTT and alkaline single cell gel electrophoresis
assays, respectively. 相似文献
6.
E. V. Smirnova A. V. Garkovenko T. V. Rakitina S. N. Berezhnoi M. V. Astapova E. A. Surina I. I. Babichenko I. A. Kostanyan V. M. Lipkin 《Russian Journal of Bioorganic Chemistry》2004,30(2):114-123
The mature differentiation factor HLDF, isolated from cultural medium, comprises 54 aa, whereas the open reading frame of mRNA encodes a 97-aa protein. We presumed that the protein translation begins from the first ATG codon, whose environment mostly meets the requirements for the initiation point. Two more ATG triplets are localized in positions 48–50 and 100–102 (numbering according to the structure of S21), i.e., in the area preceding the cDNA fragment that encodes the N-terminal fragment of the mature protein. The mRNAs of HLDF and S21 ribosomal protein have previously been shown to be highly homologous, and, therefore, their differences appear to be derived from two point deletions in the cDNA of the HLDF-encoding sequence (a G residue in position 112 and a C residue in position 224). As a result, the mature differentiation factor and RPS21 may be the products of translation from different open reading frames, the differentiation factor may be synthesized in the cell as a precursor, and its N-terminal sequence may be identical to that of RPS21. To test this hypothesis, we prepared recombinant RPS21 and the polyclonal antibodies to HLDF, full-size RPS21, and the C-terminal RPS21 peptide. Immunochemical staining by specially produced antibodies of native HL-60 cells and the same cells brought into apoptosis or differentiation confirmed that the precursor of the differentiation factor and the ribosomal S21 protein have a common N-terminal sequence and different cellular localizations. Neither an intron-containing gene nor a pseudogene with the nucleotide sequence corresponding to the HLDF cDNA was detected in the human genome or in the HL-60 cell line genome. On the basis of these facts, we propose a hypothesis of the molecular mechanism of the HLDF mRNA biosynthesis by means of posttranslational modifications of pre-mRNA of RPS21. 相似文献
7.
Antiproliferative activity of sulfated polysaccharide isolated from an enzymatic digest of Ecklonia cava on the U-937 cell line 总被引:1,自引:0,他引:1
Yasantha Athukorala Gin Nae Ahn Young-Heun Jee Gi-Young Kim Soo-Hyun Kim Jin-Hwan Ha Jung-Sook Kang Ki-Wan Lee You-Jin Jeon 《Journal of applied phycology》2009,21(3):307-314
A sulfated polysaccharide purified from a brown alga Ecklonia cava, having high anticoagulant activity was investigated for its antiproliferative effect on murine colon carcinoma (CT-26),
human leukemic monocyte lymphoma (U-937), human promyelocytic leukemia (HL-60), and mouse melanoma (B-16) cell lines. The
sulfated polysaccharide isolated and purified from an enzymatic extract of E. cava had a good selective tumor cell growth inhibition effect; its effect on HL-60 and U-937 was especially promising. The IC50 value for the sulfated polysaccharide from E. cava (ECSP) on U-937 was 43.9 μg mL−1. The presence of the sample in the cell culture media stimulated the induction of apoptosis, revealed by nuclear staining
with Hoechst 33342. The apoptosis induction was confirmed by the cell cycle analysis, while pronounced sub-G1 phase arrests
of 9.5% and 13.8% were also clearly observed when the cells were treated at 15 and 30 μg mL−1 of ECSP in the U-937 cell line, respectively. After a 24-h incubation period, ECSP dose-dependently enhanced the DNA fragmentation
on the U-937 cell line as observed in the agarose gel electrophoresis assay. To rule out the action mechanism of ECSP for
its anticancer activity, some western blot analyses were conducted with several antibodies (caspase-7, caspase-8, Bax, Bcl-xL,
and PARP) and ECSP had a clear effect on the caspase -7 and 8 which cleave protein substrates, including PARP, an inducer
of apoptosis responsible for DNA cleavage. Moreover, ECSP controlled the cellular transmembrane molecules like Bax and Bcl-xL.
Taken together, the above results demonstrate that the apoptosis for antiproliferative effect of ECSP was clearly induced
on U-937 cells. 相似文献
8.
Tetrahydropapaveroline (THP), a metabolite of dopamine, has been suspected to be associated with dopaminergic neurotoxicity of L-DOPA. THP induced apoptosis in human leukemia cell line HL-60 cells, but did not in its hydrogen peroxide (H2O2)-resistant clone HP100. THP-induced DNA ladder formation in HL-60 cells was inhibited by a metal chelator. THP induced damage to 32P-labeled DNA fragments in the presence of metals. In the presence of Fe(III)EDTA, THP caused DNA damage at every nucleotide. The DNA damage was inhibited by free hydroxy radical (·OH) scavengers and catalase, suggesting that the Fe(III)EDTA-mediated DNA damage is mainly due to ·OH generation. In the presence of Cu(II), THP caused DNA damage mainly at T and G of 5′-TG-3′ sequence. The inhibitive effect of catalase and bathocuproine on Cu(II)-mediated DNA damage suggested that H2O2 and Cu(I) participate in the DNA damage. This study demonstrated that THP-induced apoptosis via reactive oxygen species generated from reaction of H2O2 and metals plays an important role in cytotoxicity of L-DOPA. 相似文献
9.
As already shown, some inducers of the differentiation of promyelocytic cells along the granulocytic pathway, such as dimethylsulphoxide
(DMSO) or all-trans retinoic acid, can enhance propagation of granulocytic ehrlichiae in HL-60 cell cultures. This study was conducted to prove
whether sodium valproate, a salt of di-n-propylacetic acid (VPA) known to trigger cellular differentiation in several solid and hematopoietic malignancies is similarly
efficient in ehrlichial cultures. Two cell lines derived from HL-60, that is, low-passage undifferentiated HL-60 (HL-60F)
and high-passage HL-60 spontaneously differentiated towards monocytic phenotype (HL-60J) were grown in RPMI 1640 medium supplemented
with 10% FBS. The respective HL-60F and HL-60J IC50-values for NaVPA were estimated to be 0.8 and 2.2 mM under these culture conditions; to stimulate the differentiation, the
respective doses of 0.3 and 1.2 mM were then applied. When the NaVPA-treated cells of both lines were challenged with an ehrlichial
laboratory strain (HGE), maintained in splenectomized NMRI mice, the respective 1–2 and ≤0.1% primary infection rates in HL-60F
and HL-60J cultures were observed 3 days post-inoculation. In comparison, only rare (≤0.1%) infected HL-60F and no infected
HL-60J cells were recorded under the same experimental conditions in untreated control cultures. HGE continuously propagated
in NaVPA-supplemented HL-60F cultures remained infectious to mice at least up to the 95th passage (12 months). NaVPA can thus
facilitated continuous propagation of granulocytic ehrlichiae in cell cultures without a substantial loss of infectiveness.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
10.
Human leukemia promyelocytic HL-60 cells differentiate into granulocytes when cultured with 1.25% dimethyl sulfoxide for 3
d. The radioactive Na2
75SeO3 incorporation and the amount of total proteins were interrelated in both promyelocytic and granulocytic HL-60. Promyelocytic
cells had four times higher75Se incorporation and 34% more protein synthesis than the granulocytic cells on the fifth culturing day. The enzyme activities
of glutathione peroxidase (GSH-Px, E.C. 1.11.1.9) and thioredoxin reductase (TrxR, E.C. 1.6.4.5) in both types of cells increased
significantly and approached steady stage on the third day. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (PAGE)
analysis and autoradiography of the proteins from the cells revealed three proteins with molecular weights of57, 28, and 21 kDa, respectively. These three75Se-labeled proteins were present in both types of cells. The proteins from HL-60 cells were separated by DEAE-Sepharose and
2′5′-ADP-Sepharose columns. The purified 57-kDa protein had TrxR activity of 0.744 Μmol 5′-thionitrobenzoic acid (TNB) formed/min/mg
protein and two isoelectric points at pH 5.9 and 6.0. These results suggest that TrxR is one of the selenoproteins in both
promyelocytic and granulocytic HL-60 cells. 相似文献
11.
Zhou Yueqin Yang Xiaotong Li Xuquan Feng Huiqin Mi Ke Yang Qingyao 《Frontiers of Biology in China》2006,1(3):275-279
Five ethanolic extracts from the mycelia of Ganoderma lucidum, G. tsugae, G. oerstedii, G. subamboinense, and G. resinaceum were respectively studied on their anticancerous activities against leukemic HL-60 cell line in vitro. Results showed that
all five extracts potently inhibited HL-60 proliferation. The extract from G. lucidum mycelia exerted the highest activity. Annexin V/PI bivariate flow cytometric analysis further revealed that the five extracts
significantly induced early apoptosis in HL-60 cells. The results illustrate that not only G. lucidum but also other Ganoderma species can inhibit cancer cells, and their mechanisms are related to induction of apoptosis.
__________
Translated from Journal of Shanghai Normal University (Natural Sciences), 2005, 34(2): 77–81 [译自: 上海师范大学学报 (自然科学版), 2005, 34(2): 77–81] 相似文献
12.
Fred W. Perrino Dan J. Mazur Heather Ward Scott Harvey 《Cell biochemistry and biophysics》1999,30(3):331-352
The polymerization of nucleotide analogs into DNA is a common strategy used to inhibit DNA synthesis in rapidly dividing tumor
cells and viruses. The mammalian DNA polymerases catalyze the insertion of the arabinofuranosyl analogs of dNTPs (aranucleotides)
into DNA efficiently, but elongate from the 3′ aranucleotides poorly. Slow elongation provides an opportunity for exonucleases
to remove aranucleotides. The exonuclease activity associated with DNA polymerase δ removes araCMP from 3′ termini with the
same efficiency that it removes a paired 3′ deoxycytosine suggesting that the proofreading exonucleases associated with DNA
polymerases might remove aranucleotides inefficiently. A separate 30 kDa exonuclease has been purified from mammalian cells
that removes araCMP from 3′ termini. The activity of this enzyme in the cell could remove aranucleotides from 3′ termini of
DNA and decrease the efficacy of the analogs. Inhibition analysis of the purified exonuclease shows that this enzyme is inhibited
by thioinosine monophosphate (TIMP) with aK
i=17 μM. When high TIMP levels are generated in HL-60 cells, incorporation of araC in DNA is increased about 16-fold relative to
total DNA synthesis. This increased araC in DNA is likely a result of exonuclease inhibition in the cell. Thus, exonucleases
in cells might play an important role in removing aranucleotides inserted by DNA polymerases. 相似文献
13.
Kostanian IA Astapova MV Navolotskaia EV Lepikhova TN Dranitsyna SM Telegin GB Rodionov IL Baĭdakova LK Zolotarev IuA Molotkovskaia IM Lipkin VM 《Bioorganicheskaia khimiia》2000,26(7):505-511
Six-membered peptide fragment TGENHR (HLDF-6) was identified in the HL-60 cell culture of human promyelocyte leukemia treated with retinoic acid when studying the differentiation factor HLDF of this cell line. HLDF-6 retains the ability of the full-size factor to induce the differentiation and arrest the proliferation of the starting HL-60 cells. It was shown that the synthetic peptide HLDF-6 has no specific receptors on the surface of the HL-60 cells but can affect the binding of interleukin IL-1 beta, a cytokine involved in proliferation, to the cell surface. It was found on a model of transplantable NSO myeloma that HLDF-6 has an antitumor activity. 相似文献
14.
Minoru Morikawa Naoki Harada Gen-Ichiro Soma Takeshi Yoshida 《In vitro cellular & developmental biology. Plant》1990,26(7):682-690
Summary The human leukemic cells HL-60, U937, KG-1 and THP-1 incubated with transforming growth factor-β1 (TGF-β1) were studied by
examining cell surface antigens and macrophage-specific activities. The addition of 0.5 ng/ml (20 pM) of TGF-β1 with 1α,25-dihydroxyvitamin D3 [1α, 25(OH)2D3] induced more Leu-M3 (CD14)-positive cells (approximately 80%) than 5×10−8
M 1α,25(OH)2D3 alone did (30 to 50%), although original HL-60 cells did not express any Leu-M3 antigen at all. Tumor necrosis factor-α (TNF-α)
with TGF-β1 and 1α,25(OH)2D3 was found to potentiate the expression of these surface antigens. Furthermore, the phagocytic activity was also induced strongly.
The expression of CR3 (CD11b) antigen was also increased, and all Leu-M3-positive cells were found CR3-positive when HL-60,
U937, and THP-1 cells were treated with these stimulants. In contrast, CR3 but not Leu-M3 was induced in KG-1 cells after
the same treatment. This may indicate that the responsiveness of leukemic cells to TGF-β1 and 1α,25(OH)2D3 might vary depending on a differentiation stage of the target cells. Furthermore, K562 cells originated from a more undifferentiated
precursor, were not able to respond to these two inducers. These results suggested that some of TGF-β superfamily proteins
might represent potent modulators in hematopoiesis, especially in the development of monocytes-macrophages or their precursors. 相似文献
15.
《Phytomedicine》2015,22(5):545-552
BackgroundNatural products are one of the most important sources of drugs used in pharmaceutical therapeutics. Screening of several natural products in the search for novel anticancer agents against human leukemia HL-60 cells led us to identify potent apoptosis-inducing activity in the essential oil fraction from Artemisia capillaris Thunb. flower.MethodsThe cytotoxic effects of extracts were assessed on human leukemia HL-60 cells by XTT assay. Induction of apoptosis was assessed by analysis of DNA fragmentation and nuclear morphological change. The plant name was checked with the plant list website (http://www.theplantlist.org).ResultsA purified compound from the essential oil fraction from Artemisia capillaris Thunb. flower that potently inhibited cell growth in human leukemia HL-60 cells was identified as capillin. The cytotoxic effect of capillin in cells was associated with apoptosis. When HL-60 cells were treated with 10−6 M capillin for 6 h, characteristic features of apoptosis such as DNA fragmentation and nuclear fragmentation were observed. Moreover, activation of c-Jun N-terminal kinase (JNK) was detected after treatment with capillin preceding the appearance of characteristic properties of apoptosis. Release of cytochrome c from mitochondria was also observed in HL-60 cells that had been treated with capillin.ConclusionCapillin induces apoptosis in HL-60 cells via the mitochondrial apoptotic pathway, which might be controlled through JNK signaling. Our results indicate that capillin may be a potentially useful anticancer drug that could enhance therapeutic efficacy. 相似文献
16.
Zhokhov SS Kostanyan IA Gibanova NV Surina EA Rodionov IL Storozheva ZI Proshin AT Babichenko II Lipkin VM 《Biochemistry. Biokhimii?a》2004,69(8):861-869
Previously we identified a six-membered fragment 354TQVEHR359 of the C-terminal part of the PEDF (Pigment Epithelium-Derived Factor) differentiation factor molecule that shares homology with fragment 41TGENHR46 of the HLDF (Human Leukemia Differentiation Factor) differentiation factor molecule, which is responsible for its differentiation activity. HLDF has been isolated from the culture medium of human promyelocytic leukemia cell line HL-60. Hexapeptides HLDF-6 (TGENHR) and PEDF-6 (TQVEHR) corresponding to these HLDF and PEDF molecule fragments, which were previously shown to induce cell differentiation (Kostanyan et al. (2000) Russian Journal of Bioorganic Chemistry, 26, 505-511), also have neuroprotective properties. Both peptides prevent degeneration of Purkinje cells of rat cerebellar vermis upon chemical hypoxia induced by sodium azide in vivo; this effect is also observed on a behavioral level. Peptide HLDF-6 but not PEDF-6 promotes survival of HL-60 cells upon chemical hypoxia. Peptides HLDF-6 and PEDF-6 affect different second messenger biosynthesis systems in HL-60 cells. HLDF-6 diminishes cyclic AMP level in those cells due to adenylate cyclase inhibition, while PEDF-6 inhibits phosphatidylinositol-specific phospholipase C stimulated by aluminum tetrafluoride anions. 相似文献
17.
R Zhou Y Wang A Gruber R Larsson E Casta?os-Vèlez E Liliemark 《Cancer immunology, immunotherapy : CII》1999,16(3):191-198
In order to further elucidate the, roles of DNA topoisomerase II (topo II) subtypes, α and β, as drug targets in chemotherapy,
we have determined the enzyme levels in K562 cells selected for resistance to mitoxantrone (K562/Mxn), daunorubicin (K562/Dnr)
and idarubicin (K562/Ida 20 and K562/Ida 60), as well as topo II-DNA complex formation, DNA damage and cytotoxicity, induced
by topo II interactive agents, for example etoposide, teniposide, mitoxantrone and amsacrine. As compared to the parental
cells, topo IIα/β protein levels in K562/Mxn, K562/Dnr, K562/Ida 20 and 60 lines, measured with Western blot, were 17/67%,
85/88, 24/31% and 10/7% respectively. DNA damage, determined by DNA unwinding technique, induced by teniposide and amsacrine
correlated with both topo IIα/β protein levels (r
2=0.8/0.9,P=0.03/0.01 andr
2=0.8/0.9,P=0.04/0.01, respectively). Topo II-DNA complex formation induced by all studied drugs correlated with topo IIβ protein levels
(r
2-range 0.8–0.9,P-range 0.01–0.04), while the correlation with topo IIα was weaker. Topo IIα/β protein levels tended to show an inverse correlation
with the cytotoxicity of etoposide (r
2=−0.9/−0.7,P=0.01/0.06). The overall topo II-DNA complex formation correlated with drug-induced DNA damage (r
2=0.9,P=0.0001), whilst not with the cytotoxicity.
Our findings indicate that both topo II isozymes are the targets of the antitumor agents studied, and of potential clinical
relevance for prediction of treatment efficacy. They could play a role in tailored chemotherapy. 相似文献
18.
Kostanian IA Zhokhov SS Astapova MV Dranitsyna SM Bogachuk AP Baĭdakova LK Rodionov IL Baskin II Golubeva ON Tombran-Tink J Lipkin VM 《Bioorganicheskaia khimiia》2000,26(8):563-570
It was shown that the full-size neurotrophic factor from pigment epithelium (PEDF) induces the cell differentiation of the human promyelocyte leukemia cell line HL-60. A structural analysis of PEDF revealed in its C-terminal region a six-membered peptide fragment PEDF-(352-357) (PEDF-6) whose sequence is highly homologous to the 41-46 fragment of the active site of the human leukocyte differentiation factor HLDF (HLDF-6). The biological effect of PEDF and synthetic peptides PEDF-6 and HLDF-6 on the HL-60 cells and the early gastrula ectoderm of Xenopus laevis embryos was studied. On the basis of the structural and functional homologies of HLDF, PEDF, and their homologous peptides and the computer models of the spatial structures of the full-size PEDF and the PEDF with the C-terminal fragment split off tby the cleavage of the Leu380-Thr381 bond in the serpin loop, a hypothesis on the functional role of the serpin loop in PEDF was put forward. 相似文献
19.
Mineralization of pentachlorophenol in a contaminated soil by Pseudomonas sp UG30 cells encapsulated in κ-carrageenan 总被引:2,自引:0,他引:2
M B Cassidy H Mullineers H Lee J T Trevors 《Journal of industrial microbiology & biotechnology》1997,18(1):43-48
A fermentation process in Escherichia coli for production of supercoiled plasmid DNA for use as a DNA vaccine was developed using an automated feed-back control nutrient
feeding strategy based on dissolved oxygen (DO) and pH. The process was further automated through a computer-aided data
processing system to regulate the cell growth rate by controlling interactively both the nutrient feed rate and agitation
speed based on DO. The process increased the total yield of the plasmid DNA by approximately 10-fold as compared to a manual
fed-batch culture. The final cell yield from the automated process reached 60 g L−1 of dry cell weight (OD600 = 120) within 24 h. A plasmid DNA yield of 100 mg L−1 (1.7 mg g−1 cell weight) was achieved by using an alkaline cell lysis method. Plasmid yield was confirmed using High Performance Liquid
Chromatography (HPLC) analysis. Because cells had been grown under carbon-limiting conditions in the automated process,
acetic acid production was minimal (below 0.01 g L−1) throughout the fed-batch stage. In contrast, in the manual process, an acid accumulation rate as high as 0.36 g L−1 was observed, presumably due to the high nutrient feed rates used to maintain a maximum growth rate. The manual fed-batch
process produced a low cell density averaging 10–12 g L−1 (OD600 = 25–30) and plasmid yields of 5–8 mg L−1 (approximately 0.7 mg g−1 cells). The improved plasmid DNA yields in the DO- and pH-based feed-back controlled process were assumed to be a result
of a combination of increased cell density, reduced growth rate (μ) from 0.69 h−1 to 0.13 h−1 and the carbon/nitrogen limitation in the fed-batch stage. The DO- and pH-based feed-back control, fed-batch process has
proven itself to be advantageous in regulating cell growth rate to achieve both high cell density and plasmid yield without
having to use pure oxygen. The process was reproducible in triplicate fermentations at both 7-L and 80-L scales.
Received 22 March 1996/ Accepted in revised form 20 September 1996 相似文献
20.
Lipopolysaccharide of Escherichia coli, polyamines, and acetic acid stimulate cell proliferation in intestinal epithelial cells 总被引:1,自引:0,他引:1
Jaime Olaya Vadim Neopikhanov Andrés Uribe 《In vitro cellular & developmental biology. Animal》1999,35(1):43-48
Summary Our aim was to examine whether lipopolysaccharide of Escherichia coli, polyamines of dietetic and/or bacterial origin, and products of the bacterial metabolism influence cell proliferation in
epithelial cells from the colon and small intestine. Lipopolysaccharide of Escherichia coli 0111:B4 was incubated with cultures from human colonic mucosa. The mitoses were arrested with Vincristine and the total number
of metaphases per crypt was counted. In addition, lipopolysaccharide was incubated with a human colonic epithelial cell line
from adenocarcinoma (LS-123 cells) and with a nontransformed small intestinal cell line from germ-free rats (IEC-6 cells)
for 24 h. In the last 4 h, the cells were labeled with tritiated thymidine. The cells were incubated with putrescine, cadaverine,
and spermidine at 10−11–10−3
M and with acetic acid (10−5–10−1
M), acetaldehyde (10−10–10−4
M) and ammonium chloride (1–20 mM). Lipopolysaccharide of Escherichia coli increased the number of arrested metaphases in human colonic crypts and DNA synthesis in L-123 and IEC-6 cells (P<0.001). All polyamines increased DNA synthesis in the colonic and small intestinal cell lines, the effects being more marked
for putrescine (P<0.001). The higher concentrations of acetic acid increased DNA synthesis in both epithelial cell lines (P<0.001). Acetaldehyde slightly decreased DNA synthesis in LS-123 cells at cytotoxic concentrations. Ammonium chloride did
not significantly affect DNA synthesis. The final concentration of nonionized ammonia was less than 3%. It is concluded that
lipopolysaccharides of Escherichia coli and intraluminal factors derived from microorganisms increase cell proliferation in human colonic crypts and intestinal epithelial
cell lines. 相似文献