1.Media optimization for the novel antimicrobial peptide by Bacillus sp. fmbJ224.
Juan SHEN ; Zhao-Xin LU ; Xiao-Mei BIE ; Feng-Xia LÜ ; Xian-Qing HUANG
Chinese Journal of Biotechnology 2005;21(4):609-614
The novel antimicrobial peptide in submerged fermentation by Bacillus sp. fmbJ224 is strongly influenced by many internal and external factors, namely medium constituents and fermentation conditions. In this study, Plackett-Burman design was undertaken to evaluate the effects of the seventeen factors. By the statistical regression analysis, the significant factors affecting the novel antimicrobial peptide in submerged fermentation by Bacillus sp. fmbJ224 were determined as follows: glucose, NH4NO3, glutamic acid, CaCl2, MnSO4. In the second phase of the optimization process, a response surface methodology (RSM) was used to optimize the above critical internal factors, and to find out the optimization concentraction levels and the relationships between these factors. By solving the quadratic regression model equation using appropriate statistic methods, the optimal concentration of the variables were determined as: 8.13 g/L glucose, 6.14 g/L NH4NO3, 4.2 g/L glutamic acid, 3.98 mg/L CaCl2, 4.87 mg/L MnSO4. The content of the novel antimicrobial peptide was increased from 1304.21 microg/mL to 1487.58 microg/mL. The experimental data under various conditions have validated the theoretical values.
Anti-Infective Agents
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metabolism
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Bacillus
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growth & development
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metabolism
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Cell Culture Techniques
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methods
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Culture Media
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Fermentation
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Peptides
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metabolism
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Regression Analysis
2.Antimicrobial metabolites from marine microorganisms.
Prasanna HABBU ; Vijayanand WARAD ; Rajesh SHASTRI ; Smita MADAGUNDI ; Venkatrao H KULKARNI
Chinese Journal of Natural Medicines (English Ed.) 2016;14(2):101-116
Marine ecological niches have recently been described as "particularly promising" sources for search of new antimicrobials to combat antibiotic-resistant strains of pathogenic microorganisms. Marine organisms are excellent sources for many industrial products, but they are partly explored. Over 30 000 compounds have been isolated from marine sources. Bacteria, fungi, and cyanobacteria obtained from various marine sources secret several industrially useful bioactive compounds, possessing antibacterial, antifungal, and antimycobacterial activities. Sustainable cultivation methods for promising marine organisms and biotechnological processes for selected compounds can be developed, along with the establishment of biosensors for monitoring the target compounds. The semisynthetic modifications of marine-based bioactive compounds produce their new derivatives, structural analogs and mimetics that could serve as novel lead compounds against resistant pathogens. The present review focuses on promising antimicrobial compounds isolated from marine microbes from 1991-2013.
Anti-Infective Agents
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chemistry
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metabolism
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pharmacology
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Bacteria
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chemistry
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isolation & purification
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metabolism
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Fungi
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chemistry
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isolation & purification
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metabolism
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Seawater
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microbiology
3.Toll-like Receptors and Antimicrobial Peptides Expressions of Psoriasis: Correlation with Serum Vitamin D Level.
Sue Kyung KIM ; Sun PARK ; Eun So LEE
Journal of Korean Medical Science 2010;25(10):1506-1512
To evaluate the association of Toll-like receptors (TLRs), antimicrobial peptides (AMPs) and vitamin D receptors (VDRs) in psoriasis, lesional (PP) and perilesional skin (PN) from psoriasis, atopic dermatitis (AD) patients and healthy controls (NN) were studied by immunohistochemistry. Compared with PN, AD and NN skin, dysregulated expression of TLRs, AMPs and VDR was detected in PP skin. Noteworthy, our results showed altered correlation between TLR2 and VDR expression in PP and PN skin. Human beta defensin 2 (HBD2) and cathelicidin (LL-37) expressions in the PP skin were higher in serum vitamin D sufficient (VDS) groups than serum vitamin D deficient (VDD) groups. Negative correlation was found between TLR2 and VDR expression in the PP skin of VDD groups. However, positive correlation was noted in the PP skin of VDS groups. Based on the present results, therapies targeting the activity of TLRs, AMPs and vitamin D, including modulation of the TLR-VDR pathways, might provide new therapeutic approaches to the psoriasis and other inflammatory skin diseases.
Anti-Infective Agents/*metabolism
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Antimicrobial Cationic Peptides/*metabolism
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Female
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Humans
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Male
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Psoriasis/*metabolism
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Receptors, Calcitriol/metabolism
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Toll-Like Receptors/*metabolism
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Vitamin D/*blood
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beta-Defensins/metabolism
4.Thirteen new peptaibols with antimicrobial activities from Trichoderma sp.
Pan TANG ; Dan HUANG ; Kai-Xuan ZHENG ; Dan HU ; Ping DAI ; Chuan-Hui LI ; Sheng-Ying QIN ; Guo-Dong CHEN ; Xin-Sheng YAO ; Hao GAO
Chinese Journal of Natural Medicines (English Ed.) 2023;21(11):868-880
From the fungus Trichoderma sp., we isolated seven novel 18-residue peptaibols, neoatroviridins E-K (1-7), and six new 14-residue peptaibols, harzianins NPDG J-O (8-13). Additionally, four previously characterized 18-residue peptaibols neoatroviridins A-D (14-17) were also identified. The structural configurations of the newly identified peptaibols (1-13) were determined by comprehensive nuclear magnetic resonance (NMR) and high-resolution electrospray ionization tandem mass spectrometry (HR-ESI-MS/MS) data. Their absolute configurations were further determined using Marfey's method. Notably, compounds 12 and 13 represent the first 14-residue peptaibols containing an acidic amino acid residue. In antimicrobial assessments, all 18-residue peptaibols (1-7, 14-17) exhibited moderate inhibitory activities against Staphylococcus aureus 209P, with minimum inhibitory concentration (MIC) values ranging from 8-32 μg·mL-1. Moreover, compound 9 exhibited moderate inhibitory effect on Candida albicans FIM709, with a MIC value of 16 μg·mL-1.
Peptaibols/chemistry*
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Trichoderma/metabolism*
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Tandem Mass Spectrometry/methods*
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Anti-Infective Agents/pharmacology*
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Spectrometry, Mass, Electrospray Ionization/methods*
5.Differential proteomics on synthetic antimicrobial decapeptide against Streptococcus mutans.
Yi LIU ; Wei FEI ; Yanjun WANG ; Yandong MU ; Hongkun WU
West China Journal of Stomatology 2015;33(2):187-191
OBJECTIVETo compare the protein profiles between decapeptide-treated and untreated planktonic cells of Streptococcus mutans (S. mutans) by differential proteomic analysis to determine and identify the key proteins.
METHODSIn our previous study, we investigated decapeptide (KKVVFKVKFK-NH2), which was a novel adenosine monophosphate. Compared with other oral pathogens tested, decapeptide had a preferential antibacterial activity against S. mutans. It also inhibited S. mutans biofilm formation and reduced the one-day developed biofilm. In the present study, we first synthesized decapeptide, and then compared the protein profiles between decapeptide-treated and untreated planktonic cells of S. mutans by two-dimensional gel electrophoresis and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. We also verified different expressions of key protein enolase in the protein level.
RESULTSThe results showed that decapeptide altered the protein expression of planktonic S. mutans. These proteins were functionally involved in carbohydrate degradation by glycolysis, protein folding, conjunction, transport, translation, adenosine triphosphate binding, protein binding, sequence-specific DNA binding, transcription factor activity, and two-component response regulator activity. Western blot results showed that enolase protein expression decreased obviously in decapeptide-treated cells of S. mutans.
CONCLUSIONThe protein expression of S. mutans significantly changed after synthetic antimicrobial decapeptide treatment, suggesting that decapeptide may present a preferential effect on oral caries by changing the expression of certain key proteins, such as enolase protein.
Anti-Bacterial Agents ; Anti-Infective Agents ; Biofilms ; Dental Caries ; Depsipeptides ; genetics ; Electrophoresis, Gel, Two-Dimensional ; Oligopeptides ; genetics ; Proteomics ; Streptococcus mutans ; metabolism
6.Advances in researches on epididymal WFDC-type serine protease inhibitors.
Juan LIU ; Hai-Yan WANG ; Jian-Yuan LI
National Journal of Andrology 2008;14(11):1027-1030
Sperm maturation in the epididymis is regulated by changes of luminal ion concentration and processing of sperm surface membrane by several glycosidases and proteases, and the actions of the proteases are controlled by protease inhibitors present in specific areas of the epididymis. WFDC-type serine protease inhibitors that are highly expressed in the epididymis play an important role in natural immunity and male reproduction. This paper gives an overview of the structure and function of the protein and its application prospects in the development of drugs for male reproductive tract infection and immunocontraception.
Anti-Infective Agents
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therapeutic use
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Contraceptive Agents
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Epididymal Secretory Proteins
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metabolism
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Epididymis
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chemistry
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metabolism
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Humans
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Male
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Serine Proteinase Inhibitors
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genetics
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metabolism
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therapeutic use
7.Accumulation of ciprofloxacin and lomefloxacinin fluoroquinolone-resistant strains of Escherichia coli.
Peiyuan XIA ; Ping FENG ; Li ZHONG ; Xiaojü LU ; Bingjün LEI
Chinese Medical Journal 2002;115(1):31-35
OBJECTIVETo evaluate the role of outer membrane protein (Omp) F-deficiency and active efflux in the accumulation of hydrophilic fluoroquinolones ciprofloxacin (CPLX) and lomefloxacin (LMLX) in resistant E. coli strains.
METHODSFluoroquinolone accumulation in bacteria and the effect of active efflux were measured by a fluorescence method. The outer membrane proteins of the bacteria were analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). E. coli strains in this study included control strains JF701 and JF703 that are OmpC- or OmpF-deficient mutants of E. coli K-12, respectively, and the fluoroquinolone susceptible strain the fluoroquinolone susceptible strain of Escherichia coli (Ecs) and its in vitroselected resistant strains R2 and R256, and the clinical resistant isolates R5 and R6.
RESULTSThe steady-state accumulation concentration of each drug in Ecs appeared to be the same as in JF701, while in the OmpF-deficient strain JF703, it was 1/5 CPLX or 1/2 LMLX lower than that in JF701, but JF703 was still susceptible to fluoroquinolones. On the other hand, compared with susceptible strains, a 2- to 10-fold decrease in the accumulation of each drug was found in the resistant strains except R2, in which the accumulation was slightly higher than in JF703. After the addition of 2,4-dinitrophenol (DNP), accumulation of each drug increased, especially in resistant strains, indicating that the function of the active efflux (pump) system in these bacteria had been enhanced dramatically. Furthermore, both OmpF and OmpC in Ecs, OmpF-deficiency in R2 and R256 and OmpC-deficiency in R5 and R6 were observed.
CONCLUSIONThe decreased accumulation of hydrophilic fluoroquinolones in E. coli involved OmpF-deficiency and active efflux (pump), and the latter may be an important factor.
2,4-Dinitrophenol ; pharmacology ; Anti-Infective Agents ; metabolism ; pharmacology ; Ciprofloxacin ; metabolism ; pharmacology ; Drug Resistance, Bacterial ; Escherichia coli ; drug effects ; metabolism ; Fluoroquinolones ; Porins ; physiology ; Quinolones ; metabolism ; pharmacology
8.Absorption properties and mechanism of trolline and veratric acid and their implication to an evaluation of the effective components of the flowers of Trollius chinensis.
Li-Jia LIU ; Xiu-Wen WU ; Ru-Feng WANG ; Yu-Shuai PENG ; Xin YANG ; Jun-Xiu LIU
Chinese Journal of Natural Medicines (English Ed.) 2014;12(9):700-704
AIM:
To study the absorption properties and mechanism of two important components, trolline and veratric acid, from the flowers of Trollius chinensis, in order to better understand the contribution of these two compounds to the effectiveness of these flowers.
METHOD:
The human Caco-2 cell monolayer model was employed to study the transport of trolline and veratric acid from apical side (AP) to basal side (BL), and from BL to AP by determining the transport rates as the function of time and concentration and calculating apparent permeability coefficients (Papp).
RESULTS:
Trolline and veratric acid were transported across Caco-2 cell monolayer through different mechanisms in a concentration dependent manner. Trolline was transported at a Papp level of 10(-6) cm·s(-1) with a Papp AP→BL/Papp BL→AP ratio of more than 1.8 or less than 0.8, while veratric acid was transported at a Papp level of 10(-5)cm·s(-1) with a Papp AP→BL/Papp BL→AP ratio of close to 1.0.
CONCLUSION
Trolline is moderately absorbed through an associative mechanism involving active and passive transport, and veratric acid is well-absorbed mainly through passive diffusion. These factors should be taken into account when chemically assessing the pharmacodynamic material basis of the flowers of T. chinensis.
Alkaloids
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metabolism
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pharmacology
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Anti-Infective Agents
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metabolism
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pharmacology
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Anti-Inflammatory Agents
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metabolism
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pharmacology
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Biological Transport
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Caco-2 Cells
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Flowers
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chemistry
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Humans
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Intestinal Absorption
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Plant Extracts
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metabolism
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pharmacology
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Ranunculaceae
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chemistry
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Vanillic Acid
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analogs & derivatives
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metabolism
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pharmacology
9.Mechanisms and management of drug induced liver injury in children.
Chinese Journal of Pediatrics 2014;52(8):583-585
Anti-Bacterial Agents
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adverse effects
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Anti-Infective Agents
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adverse effects
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Anti-Inflammatory Agents
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adverse effects
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Biomarkers
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blood
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Chemical and Drug Induced Liver Injury
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diagnosis
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epidemiology
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Child
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Drug-Related Side Effects and Adverse Reactions
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Humans
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Liver
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drug effects
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metabolism
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pathology
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Pediatrics
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Risk Factors
10.Optimizing conditions for the expression of human beta defensin 3 and des-pGlu1-Brazzein in Escherichia coli and analysis of their activity.
Chunli LI ; Xueli XU ; Zhenyu ZHENG ; Weidong ZHAO
Chinese Journal of Biotechnology 2008;24(3):485-490
The inductive conditions for the flask-shaking of E.coli BL21-pET-hBD3-Bra had been optimized, at the same time, the expressed protein had been purified and analyzed. The effect of three factors which were IPTG concentration, induction time and temperature on growth of strain and on the yield of hBD3-Bra was analyzed in detail. The result indicated that the concentration of IPTG had little effect on the growth and the expression of target protein between 0.2-1 mmol/L, Biomass would be improved as time passed, but the target protein didn't increase obviously as the same time, temperature was the most important factor, the expressed level of hBD3-Bra, as high as about 35% of total cell protein, could be gained when strain was induced by IPTG under 30 degrees C. Further analysis showed the best temperature for growth was 30 degrees C-32 degrees C and for expression protein was 30 degrees C.The purified hBD3-Bra has a weak antimicrobial activity, but is 200 times sweeter than that of sucrose. After digested by thrombin and purified by affinity column, the natural des-pGlul-Brazzein also has 600-time sweetness of sucrose, and the recombinant hBD3 has a high antimicrobial activity again E. coli and S. aureus.
Anti-Infective Agents
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Escherichia coli
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genetics
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metabolism
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Humans
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Plant Proteins
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biosynthesis
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genetics
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Recombinant Fusion Proteins
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biosynthesis
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genetics
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pharmacology
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Sweetening Agents
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Temperature
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beta-Defensins
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biosynthesis
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genetics