scholarly journals Characterization of chito-oligosaccharides prepared by chitosanolysis with the aid of papain and Pronase, and their bactericidal action against Bacillus cereus and Escherichia coli

2005 ◽  
Vol 391 (2) ◽  
pp. 167-175 ◽  
Author(s):  
Acharya B. Vishu Kumar ◽  
Mandyam C. Varadaraj ◽  
Lalitha R. Gowda ◽  
Rudrapatnam N. Tharanathan
Keyword(s):  
Escherichia Coli ◽  
Growth Inhibition ◽  
Bacillus Cereus ◽  
Streptomyces Griseus ◽  
Degree Of Polymerization ◽  
Native Page ◽  
Growth Inhibitory ◽  
Growth Inhibitory Activity ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis

Papain (from papaya latex; EC 3.4.22.2) and Pronase (from Streptomyces griseus; EC 3.4.24.31) caused optimum depolymerization of chitosan at pH 3.5 and 37 °C, resulting in LMMC (low molecular mass chitosan) and chito-oligomeric–monomeric mixture. The yield of the latter was 14–16% and 14–19% respectively for papain- and Pronase-catalysed reactions, depending on the reaction time (1–5 h). HPLC revealed the presence of monomer(s) and oligomers of DP (degree of polymerization) 2–6, which was also confirmed by matrix-assisted laser-desorption ionization–time-of-flight MS. Along with the chito-oligomers, the appearance of only GlcNAc (N-acetylglucosamine) in Pronase-catalysed chitosanolysis was indicative of its different action pattern compared with papain. Fourier-transform infrared, liquid-state 13C-NMR spectra and CD analyses of chito-oligomeric–monomeric mixture indicated the release of GlcNAc/GlcNAc-rich oligomers. The monomeric sequence at the non-reducing ends of chito-oligomers was elucidated using N-acetylglucosaminidase. The chito-oligomeric–monomeric mixture showed better growth inhibitory activity towards Bacillus cereus and Escherichia coli compared with native chitosan. Optimum growth inhibition was observed with chito-oligomers of higher DP having low degree of acetylation. The latter caused pore formation and permeabilization of the cell wall of B. cereus, whereas blockage of nutrient flow due to the aggregation of chito-oligomers–monomers was responsible for the growth inhibition and lysis of E. coli, which were evidenced by scanning electron microscopy analysis. The spillage of cytoplasmic enzymes and native PAGE of the cell-free supernatant of B. cereus treated with chito-oligomeric–monomeric mixture further confirmed bactericidal activity of the latter. Use of papain and Pronase, which are inexpensive and easily available, for chitosanolysis, is of commercial importance, as the products released are of considerable biomedical value.

scholarly journals Semi-Synthesis of Small Molecules of Aminocarbazoles: Tumor Growth Inhibition and Potential Impact on p53

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1637
Author(s):  
Solida Long ◽  
Joana B. Loureiro ◽  
Carla Carvalho ◽  
Luís Gales ◽  
Lucília Saraiva ◽  
...  
Keyword(s):  
Growth Inhibition ◽  
Small Molecules ◽  
Tumor Cells ◽  
Mutant P53 ◽  
Wild Type ◽  
Naturally Occurring ◽  
Growth Inhibitory ◽  
Growth Inhibitory Activity ◽  
Amino Derivatives ◽  
Carbazole Alkaloids

The tumor suppressor p53 is inactivated by mutation in approximately 50% of human cancers. Small molecules that bind and stabilize those mutants may represent effective anticancer drugs. Herein, we report the tumor cell growth inhibitory activity of carbazole alkaloids and amino derivatives, as well as their potential activation of p53. Twelve aminocarbazole alkaloids were semi-synthesized from heptaphylline (1), 7-methoxy heptaphylline (2), and 7-methoxymukonal (3), isolated from Clausena harmandiana, using a reductive amination protocol. Naturally-occurring carbazoles 1–3 and their amino derivatives were evaluated for their potential effect on wild-type and mutant p53 activity using a yeast screening assay and on human tumor cell lines. Naturally-occurring carbazoles 1–3 showed the most potent growth inhibitory effects on wild-type p53-expressing cells, being heptaphylline (1) the most promising in all the investigated cell lines. However, compound 1 also showed growth inhibition against non-tumor cells. Conversely, semi-synthetic aminocarbazole 1d showed an interesting growth inhibitory activity in tumor cells expressing both wild-type and mutant p53, exhibiting low growth inhibition on non-tumor cells. The yeast assay showed a potential reactivation of mutant p53 by heptaphylline derivatives, including compound 1d. The results obtained indicate that carbazole alkaloids may represent a promising starting point to search for new mutp53-reactivating agents with promising applications in cancer therapy.

Two Arabidopsis thaliana dihydrodipicolinate synthases, DHDPS1 and DHDPS2, are unequally redundant

2012 ◽  
Vol 39 (12) ◽  
pp. 1058 ◽  
Author(s):  
Susan Jones-Held ◽  
Luciana Pimenta Ambrozevicius ◽  
Michael Campbell ◽  
Bradley Drumheller ◽  
Emily Harrington ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Arabidopsis Thaliana ◽  
Growth Inhibition ◽  
Segregation Analysis ◽  
Narrow Range ◽  
Insertion Mutant ◽  
Biosynthesis Pathway ◽  
Wild Type ◽  
Exogenous Feeding ◽  
Growth Inhibitory

In Arabidopsis thalinana (L.) Heynh., DHDPS1 and DHDPS2 encode orthologous dihydrodipicolinate synthases (DHDPS), the first enzyme of the lysine (Lys) biosynthesis pathway. A TDNA insertion mutant of dhdps2 was previously reported to be viable and to accumulate free threonine (Thr). Analysis of additional TDNA insertion lines showed that dhdps1 and dhdps2 mutants are both viable and that whereas dhdps2 mutants accumulate Thr, dhdps1 plants do not. Thr-accumulation was complemented by heterologous expression of Escherichia coli DapA, indicating that the phenotype is due to reduced DHDPS activity in dhdps2. DHDPS1 contributes ~30% towards the total DHDPS activity in leaves of young plants and DHDPS2 contributes 70%; therefore, the threshold of activity resulting in Thr accumulation lies within this narrow range. dhdps1–dhdps2 double mutants could not be isolated, even after exogenous feeding with Lys. Segregation analysis indicated that gametes lacking functional DHDPS genes are defective, as are embryos. Plants carrying only a single DHDPS2 gene do not accumulate Thr, but they show a gametophytic defect that is partially rescued by Lys application. Despite the accumulation of Thr, dhdps2 seedlings are no more sensitive than wild-type plants to growth inhibition by Lys or the Lys precursor diaminopimelate. They also are not rescued by methionine at growth-inhibitory Lys concentrations. Exogenous application of Lys and methionine to dhdps2 mutants did not reduce the accumulation of Thr.

scholarly journals Molecular identification of Bifidobacterium sp. from local yoghurt and evaluation of growth inhibition activity against pathogenic bacteria

2021 ◽  
Vol 56 (3) ◽  
pp. 147-154
Author(s):  
AP Talukder ◽  
MN Haque ◽  
ML Mahmud ◽  
MAE Ekram
Keyword(s):  
Growth Inhibition ◽  
Molecular Identification ◽  
Inhibitory Activity ◽  
Pathogenic Bacteria ◽  
Inhibition Zone ◽  
Antagonistic Activity ◽  
E Coli ◽  
Growth Inhibitory ◽  
Growth Inhibitory Activity ◽  
Acinetobacter Sp

Yoghurt is a potential source of probiotic bacteria including Bifidobacterium sp. In this context, sour yoghurt sample was collected from local market in Rajshahi for molecular identification and characterization of Bifidobacterium sp. with promising antagonistic activity against pathogenic bacteria. Isolation was done on Luria broth agar media for molecular identification and revealed that isolated bacterium showed 90% similarity with Bifidobacterium sp. Antibiotic sensitivity test result revealed that isolated Bifidobacterium sp. was sensitive to erythromycin, kanamycin, gentamycin, tetracycline, ciprofloxacin, doxycycline out of eleven commercially used antibiotics. Moreover, antagonistic activity of Bifidobacterium sp. was evaluated in our present study against four pathogenic bacteriathrough disc diffusion method. Bifidobacterium sp. had relatively strong antagonistic effect (inhibition zone ≥15 mm) against Salmonella sp. with 16mm and 19mm zones of inhibition at doses of 150 and 200 μg/disc, respectively. Similarly, the isolate showed strong growth inhibitory activity against Acinetobacter sp. and E. coli with inhibition zone of 17 mm and 16 mm at dose of 200 μg/disc while moderate growth inhibitory activity was observed against Aeromonas sp. at applied four doses. Furthermore, present investigation showed that the isolated Bifidobacterium sp. had the utmost effect against Salmonella sp. and exhibited growth inhibition of understudy pathogens in such pattern Salmonella sp.>Acinetobacter sp.> E. coli> Aeromonas sp. Bangladesh J. Sci. Ind. Res.56(3), 147-154, 2021

AKTIVITAS PENGHAMBATAN PERTUMBUHAN MIKROORGANISME DARI EKSTRAK DAN FRAKSI ALGA Ulva lactuca TERHADAP Escherichia coli, Staphylococcus aureus, DAN Candida albicans

PHARMACON ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 397
Author(s):  
Brigieta Keintjem ◽  
Defny S. Wewengkang ◽  
Fatimawali Fatimawali
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Candida Albicans ◽  
Ulva Lactuca ◽  
Diffusion Method ◽  
Bioactive Substances ◽  
Growth Inhibitory ◽  
Growth Inhibitory Activity ◽  
Temperature Water

ABSTRACT Algae have long been used for the treatment of various types of diseases. Ulva lactuca is one of the algae, which contains bioactive substances as antimicrobial, antifungal, and antioxidant. This study aims to determine the microorganisms growth inhibitory activity from Ulva lactuca algae obtained from the of Lembeh Strait waters in City of Bitung against microorganisms Escherichia coli, Staphylococcus aureus and Candida albicans. Ulva lactuca algae was extracted using maceration method with ethanol solvent and fractionated with methanol, n-hexan and chloroform solvents. Testing of antimicrobial activity using agar diffusion method. The result showed that extracts and fractions of Ulva lactuca algae did not have antimicrobial activity against the microorganisms Escherichia coli, Staphylococcus aureus and Candida albicans. The chemical composition of algae is influenced by season, geographical distribution, as well as environmental factors such as temperature, water, salinity, light, nutrition, and mineral availability.Keywords: Ulva lactuca, Antimicrobials, Maseration, Fractions, Agar DiffusionABSTRAK Alga telah lama digunakan untuk keperluan pengobatan berbagai jenis penyakit.  Ulva lactuca merupakan salah satu alga yang memiliki kandungan zat bioaktif sebagai antimikroba. Penelitian ini bertujuan untuk mengetahui adanya aktivitas penghambat pertumbuhan mikroorganisme dari alga Ulva lactuca yang diperoleh dari perairan Selat Lembeh kota Bitung terhadap mikroba Escherichia coli, Staphylococcus aureus, dan Candida albicans. Alga Ulva lactuca diekstraksi menggunakan metode maserasi dengan pelarut etanol dan difraksinasi dengan pelarut methanol, n-hexan, dan kloroform. Pengujian aktivitas antimikroba menggunakan metode difusi agar. Hasil penelitian menunjukkan ekstrak dan fraksi dari alga Ulva lactuca tidak memiliki aktivitas antimikroba terhadap Escherichia coli, Staphylococcus aureus, dan Candida albicans. Komposisi kimia alga dipengaruhi oleh musim, distribusi geografis, serta faktor lingkungan seperti suhu, air, salinitasi, cahaya, nutrisi, dan ketersediaan mineral.Kata kunci : Alga Ulva lactuca, Antimikroba, Maserasi, Fraksi, Difusi Agar

THE ANTIBIOTIC ACTIVITY ASSOCIATED WITH PREPARATIONS OF DELTA HEMOLYSIN OF STAPHYLOCOCCUS AUREUS

1965 ◽  
Vol 11 (2) ◽  
pp. 203-211 ◽  
Author(s):  
Edward M. Hoffmann ◽  
Murray M. Streitfeld
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Growth Inhibition ◽  
Antibiotic Activity ◽  
Gram Positive Bacteria ◽  
Growth Inhibitory ◽  
Growth Inhibitory Activity ◽  
Highly Sensitive ◽  
Typical Strain ◽  
High Concentrations

Partially purified preparations of delta hemolysin demonstrated growth-inhibitory activity against certain Gram-positive bacteria, including certain strains of Staphylococcus aureus. Primary and replica plate assays indicated that the pattern of antibacterial activity manifested against a typical strain, highly sensitive to delta hemolysin, was that given by a typical antibiotic. Bactericidal, bacteriostatic, and stimulation zones were seen, dependent upon the lysin concentration. Certain of the delta hemolysin-producing strains of S. aureus manifested a pattern of growth inhibition wherein particular members of the cultures responded by bacteriostasis to high concentrations of lysin, while the remaining organisms showed no overt growth inhibition. Other strains of delta hemolysin-producing S. aureus were not inhibited in growth by delta hemolysin preparations.The identity of the delta hemolysins and the antibiotic material has not been established. However, analysis by paper chromatography of delta hemolysin preparations revealed at least two hemolytic substances, delta A and delta B, manifesting hemolysis of human erythrocytes and associated with antibiotic activity.

Cleavage of a hydrophilic C-terminal domain increases growth-inhibitory activity of oncostatin M

1990 ◽  
Vol 10 (5) ◽  
pp. 1882-1890
Author(s):  
P S Linsley ◽  
J Kallestad ◽  
V Ochs ◽  
M Neubauer
Keyword(s):  
Growth Inhibition ◽  
Inhibitory Activity ◽  
Oncostatin M ◽  
Site Directed Mutagenesis ◽  
Terminal Domain ◽  
Growth Inhibitory ◽  
Growth Inhibitory Activity ◽  
Processed Form

Oncostatin M is a polypeptide cytokine, produced by normal and malignant hematopoietic cells, that has several in vitro activities, including the ability to inhibit growth of cultured carcinoma cells. Here we present a structural and functional comparison of two oncostatin M-related proteins (Mr 36,000 and 32,000) secreted by COS cells transfected with oncostatin M cDNA. The smaller of these forms lacked a hydrophilic C-terminal domain comprising predominantly basic amino acids. This domain was also absent from native oncostatin M produced by U937 cells. The 32,000-Mr form of oncostatin M was not produced by cells transfected with plasmids (G195 and G196) in which a potential trypsinlike cleavage site within the hydrophilic C-terminal domain was altered by site-directed mutagenesis. A 32,000-Mr fragment was produced by trypsin treatment of the 36,000-Mr form of oncostatin M. These observations suggest that the 32,000-Mr form of oncostatin M was derived from the 227-amino-acid propeptide by proteolytic cleavage at or near the paired basic residues at positions 195 and 196. Pro-oncostatin M was equally active in radioreceptor assays as the processed form but was 5- to 60-fold less active in growth inhibition assays. Likewise, nonprocessed mutant protein encoded by plasmid G196 was equally active in the radioreceptor assays as the processed form but was five- to ninefold less active in growth inhibition assays. Thus, the highly charged C-terminal domain of pro-oncostatin M is not required for receptor binding or growth-inhibitory activity but may alter the functional properties of the molecule. Propeptide processing of oncostatin M may be important for regulating in vivo activities of this cytokine.

Growth Inhibition of a Human Myeloma Cell Line by All-transRetinoic Acid Is Not Mediated Through Downregulation of Interleukin-6 Receptors but Through Upregulation of p21WAF1

Blood ◽  
1999 ◽  
Vol 94 (1) ◽  
pp. 251-259 ◽  
Author(s):  
Yi-Hsiang Chen ◽  
Donald Lavelle ◽  
Joseph DeSimone ◽  
Shahab Uddin ◽  
Leonidas C. Platanias ◽  
...  
Keyword(s):  
Growth Inhibition ◽  
Interleukin 6 ◽  
Myeloma Cell ◽  
Stable Transfectants ◽  
Trans Retinoic Acid ◽  
All Trans Retinoic Acid ◽  
Growth Inhibitory ◽  
Growth Inhibitory Activity ◽  
Human Myeloma Cell Line ◽  
Interleukin 6 Receptor

All-trans retinoic acid (ATRA) has previously been shown to inhibit the growth of OPM-2 human myeloma cells. The growth inhibition was postulated to result from a transcriptional downregulation of interleukin-6 receptor  (IL-6R) with IL-6Rβ (gp130) unaffected. To formally test this hypothesis, an expression vector designed for constitutive IL-6R expression was constructed and used for transfection of OPM-2 cells. Six stable transfectants were cloned. The expression of IL-6R was shown by immunofluorescence with anti–IL-6R antibody and 125I-IL-6 binding. In five of six transfectant clones, cellular IL-6R was 1.5- to 6-fold higher than the parental cells, with the ligand binding affinity unchanged. While ATRA reduced IL-6R expression in the parental OPM-2 cells, it enhanced its expression in these five transfectants. The clonogenic growth of these transfectants, however, remained strongly inhibited by ATRA. Further analysis, comparing the parental OPM-2 cells and a representative transfectant, clone C5, showed that IL-6 caused rapid tyrosine phosphorylation of gp130 in both OPM-2 and C5 clones. Pretreatment with ATRA greatly reduced IL-6–induced gp130 phosphorylation in OPM-2 cells, reflecting a reduction in cellular IL-6R. In contrast, IL-6–induced gp130 phosphorylation was not reduced by ATRA pretreatment in C5 cells, indicating that the expressed IL-6R was functional. Similar to OPM-2 cells, C5 cells were sensitive to growth inhibition by dexamethasone, which was entirely reversed by exogenous IL-6, suggesting that the IL-6 postreceptor signal transduction remained intact. ATRA was further shown to upregulate p21WAF1 expression and cause dephosphorylation of the retinoblastoma protein (pRB) in both OPM-2 and C5 cells. Exogenous IL-6 also failed to reverse these effects of ATRA. Thus, the growth inhibitory activity of ATRA is not mediated through cellular IL-6R downregulation and is likely to result from a direct upregulation of p21WAF1 and consequent dephosphorylation of pRB.

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