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Comparative studies of versatile extracellular proteolytic activities of lactic acid bacteria and their potential for extracellular amino acid productions as feed supplements

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Journal of Animal Science and Biotechnology 2019年第3期10卷 789-801页

作者： Ye Heng Lim Hooi Ling Foo Teck Chwen Loh Rosfarizan Mohamad Norhani Abdullah Institute of Bioscience Universiti Putra Malaysia43400 UPMSerdangSelangorMalaysia Department of Bioprocess Technology Faculty of Biotechnology and Biomolecular SciencesUniversiti Putra Malaysia43400 UPMSerdangSelangorMalaysia Department of Animal Sciences Faculty of AgricultureUniversiti Putra Malaysia43400 UPMSerdangSelangorMalaysia Institute of Tropical Agriculture and Food Security Universiti Putra Malaysia43400 UPMSerdangSelangorMalaysia Institute of Tropical Forestry and Forest Products Universiti Putra Malaysia43400 UPMSerdangSelangorMalaysia

Background:Increasing understanding on the functions of amino acids (AA) has led to new commercial applications and expansion of the worldwide ***,the current technologies rely heavily on non-food grade microorganism and chemical synthesis for the production of *** studies reported that lactic acid bacteria (LAB) have the capability of producing AA owing to their well-established proteolytic system and amino acid biosynthesis ***,the objectives of this study were to explore the extracellular proteolytic activity of LAB isolated from various Malaysian fermented foods and their potential to produce AA extracellularly as feed ***:All the studied LAB isolates were versatile extracellular protease producers,whereby extracellular protease activities were detected from acidic to alkaline pH (pH 5,pH 6.5,pH 8) using qualitative and quantitative proteolytic *** highest proteolytic activity at pH 5 (15.76 U/mg) and pH 8 (19.42 U/mg) was achieved by Lactobacillus plantarum RG14,while Lactobacillus plantarum RS5 exhibited the highest proteolytic activity of 17.22 U/mg at pH *** for the results of AA production conducted in de Man,Rogosa and Sharpe medium and analysed by high pressure liquid chromatography system,all LAB isolates were capable of producing an array of ***,Pediococcus *** greater ability for AA production as compared to Lactobacillus ***,the studied LAB were able to produce a few major feed supplement AA such as methionine,lysine,threonine and *** TL-3 recorded the highest methionine and threonine productivity of 3.72 mg/L/h and 5.58 mg/L/h ***,*** I-UL4 demonstrated a lysine productivity of 1.24 mg/L/h,while *** TP-6 achieved up to 1.73 mg/L/h of tryptophan ***:All the 17 studied LAB isolates possessed versatile extracellular proteolytic system and have vast capability of producing various amino acids including a

关键词： Amino acid Bio-agent Extracel ular proteolytic activity Feed supplement Lactic acid bacteria Lactobacil us Pediococcus

Effects of light intensities and photoperiods on growth and proteolytic activity in purple non-sulfur marine bacterium, <i>Afifella marina</i>strain ME (KC205142)

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Advances in Bioscience and Biotechnology 2013年第10期4卷 919-924页

作者： Sujjat Al-Azad Tan Kar Soon Julian Ransangan Borneo Marine Research Institute University Malaysia Sabah Kota Kinabalu Malaysia

Afifella marina strain ME (KC205142), a purple non-sulfur bacterium was isolated from mangrove habitats of Sabah. The effects of light intensities and photoperiods on proteolytic activity in Afifella marina strain ME (KC205142) were investigated. Secretion of proteolytic enzymes in Afifella marina was preliminarily assessed by skim milk agarose media. Subsequently, light intensities, such as, dark, 1000, 1500, 2000, 2500, 3000, 3500, 4000, 4500 and 5000 lux were used to evaluate the effects on proteolytic activity in Afifella marina strain ME under anaerobic condition. After that, the effect of photoperiods on proteolytic activity was monitored under anaerobic light condition (3000 lux) at 0 h (0L/24D), 6 h (6L/18D), 12 h (12L/12D), 18 h (18L/6D) and 24 h (24L/0D) of photoperiod. The highest proteolytic activity of 74.67 U was recorded at 3000 lux illumination light intensity. The proteolytic activity in bacterium Afifella marina strain ME was positively associated with the dry cell weight. The proteolytic activity of 72.67 U in bacterium Afifella marina strain ME at 18 h (18L/6D) photoperiod is not significantly different (p > 0.05) from proteolytic activity of 74.67 U recorded at continuous light (24L/0D) condition. Light intensity of 3000 lux, culture period of 48 h and a photoperiod of 18 h (18L/ 6D) were the optimum parameters for proteolytic activity in bacterium Afifella marina strain ME.

关键词： Afifella marina Light Intensity Photoperiod proteolytic Activity Purple Non-Sulfur Bacteria

Bioactivities and ACE-inhibitory peptides releasing potential of lactic acid bacteria in fermented soy milk

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Food Production, Processing and Nutrition 2021年第1期3卷 149-162页

作者： Undhad Trupti Sujit Das Divyang Solanki Dhvany Kinariwala Subrota Hati Department of Dairy Microbiology SMC College of Dairy ScienceAnand Agricultural UniversityAnandGujarat388110India Department ofRural Development and Agricultural Production North-Eastern Hill UniversityTura CampusMeghalaya794001India Department of Biochemistry St.Xavier’s College(Autonomous)AhmedabadGujarat380009India

This study was designed to evaluate the bioactivities such asβ-glucosidase activity,α-galactosidase activity,and the growth behavior of the Lactobacillus cultures in soy milk *** Lactobacillus cultures were considered in this ***(M2)and ***(NK9)were selected due to their betterα-galactosidase,β-glucosidase activity and growth behavior in soy milk medium during ***,soy milk fermented with M2 showed higher proteolytic activity(0.67 OD)and ACE-inhibitory(48.44%)than NK9(proteolytic activity:0.48 OD and ACE-inhibitory activity:41.33%).Bioactive peptides produced during the fermentation of soy milk using the selected Lactobacillus cultures were also identified with potent ACE-inhibitory activity by MALDI-TOF spectrometry,and the identified ACE inhibitory peptide sequences from fermented soy milk were characterized using Biopep database.

关键词： α-Galactosidase β-Glucosidase proteolytic ACE-inhibitory peptides Fermentation Soy milk Lactic acid bacteria

AAV8 transduction capacity is reduced by prior exposure to endosome-like pH conditions

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Neural Regeneration Research 2021年第5期16卷 851-855页

作者： Jeffrey ALowell Kar Men Mah John LBixby Vance PLemmon Miami Project to Cure Paralysis University of MiamiMiamiFLUSA Department of Neurological Surgery University of MiamiMiamiFLUSA Department of Molecular and Cellular Pharmacology University of MiamiMiamiFLUSA

Adeno-associated virus(AAV)is an essential instrument in the neuroscientist’s toolkit,which allows delivery of DNA to provide labeling with fluorescent proteins or genetic instructions to regulate gene *** the field of neural regeneration,the transduction of neurons enables the observation and regulation of axon growth and regeneration,and in the future will likely be a mechanism for delivering molecular therapies to promote sprouting and regeneration after central nervous system *** formulations of AAV preparations permit efficient viral transduction under physiologic conditions,but an improved understanding of the mechanistic limitations of AAV transduction may facilitate production of more resilient AAV strains for investigative and therapeutic *** studied AAV transduction in the context of prior exposure of AAV serotype 8(AAV8)to environmental pH within the range encountered during endosomal endocytosis(pH 7.4 to pH 4.4),during which low pH-triggered structural and autoproteolytic changes to the viral capsid are believed to be necessary for endosome escape and virus *** to the fundamental nature of these processes,we hypothesized that premature exposure of AAV8 particles to acidic pH would decrease viral transduction of HT1080 cells in vitro,as measured by fluorescent reporter gene expression using high-content imaging *** found that increasingly acidic incubation conditions were associated with concomitant reductions in transduction efficiency,and that quantitative levels of reporter gene expression in transduced cells were similarly *** biggest decrease in transduction occurred between pH 7.4 and pH 6.4,suggesting the possible co-occurrence of a pH-associated event and viral inactivation within that *** together,these findings indicate that exposure of AAV8 to acidic pH for as little as 1 hour is deleterious to transduction *** studies are necessary to understand the pH-associated

关键词： adeno-associated virus autolytic capsid low pH protease proteolytic temperature trafficking transduction viral inactivation

Studies on bioprospecting potential of a gastropod mollusc Cantharus tranquebaricus(Gmelin,1791)

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Asian Pacific Journal of Tropical Biomedicine 2012年第10期2卷 759-764页

作者： G Sarumathi M Arumugam S Kumaresan T Balasubramanian Annamalai University Faculty of Marine SciencesCentre of Advanced Study in Marine Biology

Objective:To study the biological activities of the tissue extract of Cantharus tranquebaricus(***).Methods:Crude extract of gastropod was tested for inhibition of bacterial *** assay was carried out by disc diffusion method and the activity was measured accordingly based on the inhibition zone around the disc impregnated with gastropod *** weight of the extract was determined by using *** coagulation,Fibrin plate assay and substrate SDS-PAGE were used to determine the effect of sample on plasma coagulation,fibrin(ogen)olytic and proteolytic;***:The maximum inhibition zone(10 mm)was observed against Vibrio cholera(***)and minimum inhibition zone(2 mm)was noticed against Proteus mirablis(***).The molecular weight was determined as *** tissue extract shows proteolytic activity above 48 ***-PAGE analysis of fibrinogen after incubation with the tissue extract showed fibrinogenolytic *** plasma coagulation assay *** tissue extract showed procoagulant property and it coagulated chicken plasma within 150 s,while control took 5 min to *** 9 HU hemolytic units were found against chicken blood and also exhibit high level of brine shrimp ***:This study suggests that *** could be used as potential source for isolating bioactive compounds,since it is explored first time and found with promising results.

关键词： Antimicrobial proteolytic Fibrinolytic Hemolytic Brine shrimp lethality Cantharus tranquebaricus Plasma coagulation

The Biological Actions and Mechanisms of Brain-Derived Neurotrophic Factor in Healthy and Disordered Brains

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Neuroscience & Medicine 2014年第4期5卷 183-195页

作者： Toshiyuki Mizui Yuichiro Tanima Hiroko Komatsu Haruko Kumanogoh Masami Kojima Bio-Interface Research Group Health Research Institute National Institute of Advanced Industrial Science and Technology (AIST) Ikeda Japan Core Research for Evolutional Science and Technology (CREST) Japan Science and Technology Agency (JST) Kawaguchi Japan Global Discovery Research Neuroscience and General Medicine Product Creation Unit Eisai Product Creation Systems Eisai Co. Ltd. Tsukuba Japan

Brain-derived neurotrophic factor (BDNF) is a neurotrophin that elicits neuronal survival and differentiation, synaptic transmission, and the modulation of synaptic plasticity. The biological actions of BDNF are mediated via two distinct receptors: the high-affinity tropomyosin-related kinase B (TrkB) receptor and the low-affinity p75 neurotrophin receptor (p75NTR). Recent findings regarding the actions and mechanisms of BDNF are reviewed here. Activity-dependent synaptic plasticity, as exemplified by long-term potentiation (LTP) and long-term depression (LTD), underlies the cellular mechanism of learning and memory. An accumulating body of evidence shows that BDNF modulates synaptic plasticity. This function requires extracellular neurotrophin release, synaptic activity-dependent local protein synthesis. In addition, a precursor of BDNF, proBDNF, is emerging as a new ligand with biological activities that are distinct from those of BDNF. The proteolytic cleavage of proBDNF is also proposed as a mechanism that determines the direction of BDNF actions. This review discusses the post-translational processing of proBDNF, the modulatory roles of the human BDNF polymorphism Val66Met, recent reports of the novel mechanisms of BDNF expression, and clinical reports showing the roles of BDNF in the blood. Taken together, these data provide new insights into the biological roles of BDNF and its related molecules in the central nervous system.

关键词： Component Brain-Derived Neurotrophic Factor (BDNF) Tropomyosin-Related Kinase B (TrkB) Synaptic Plasticity Polymorphism proteolytic Cleavage

HIV aspartyl protease inhibitors as promising compounds against Candida albicans

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World Journal of Biological Chemistry 2010年第2期1卷 21-30页

作者： André Luis Souza dos Santos Laboratory of Multidisciplinary Studies on Microbial Biochemistry Department of General MicrobiologyInstitute of Microbiology Prof. Paulo de GóesFederal University of Rio de JaneiroRio de JaneiroRJ 21941-902Brazil

Cells of Candida albicans(***) can invade humans and may lead to mucosal and skin infections or to deep-seated my coses of almost all inner organs,especially in immunocompromised *** this context,both the host immune status and the ability of *** to modulate the expression of its virulence factors are relevant aspects that drive the candidal susceptibility or resistance;in this last case,culminating in the establishment of successful infection knownas *** possesses a potent arma-mentarium consisting of several virulence moleculesthat help the fungal cells to escape of the host *** is no doubt that the secretion of aspartyl-type proteases,designated as Saps,are one of the major virulence attributes produced by *** cells,since these hydrolytic enzymes participate in a wide range of fungal physiological processes as well as in different facets of the fungal-host *** these reasons,Saps clearly hold promise as new potential drug *** this hypothesis,the introduction of new anti-human immunodeficiency virus drugs of the as party l protease inhibitor-type(HIV PIs) have emerged as new agents for the inhibition of *** introduction of HIV PIs has revolutionized the treatment of HIV disease,reducing opportunistic infections,especially *** attenuation of candidal infections in HIV-infected individuals might not solely have resulted from improved immunological status,but also as a result of direct inhibition of *** *** this article,we review updates on the beneficial effects of HIV PIs against the human fungal pathogen ***,focusing on the effects of these compounds on Sap activity,growth behavior,morphological architecture,cellular differentiation,fungal adhesion to animal cells and abiotic materials,modulation of virulence factors,experimental candidiasis infection,and their synergistic actions with classical antifungal agents.

关键词： Candida albicans Aspartyl protease proteolytic inhibitors Human immunodeficiency virus Chemotherapy

Prevalence of Some Deteriorating Microorganisms in Some Varieties of Cheese

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Open Journal of Applied Sciences 2019年第7期9卷 620-630页

作者： Ayah B. Abdel-Salam Neveen S. M. Soliman Department of Food Hygiene and Control Faculty of Veterinary Medicine Cairo University Giza Egypt

Aim: This work throws light on the deteriorating microorganisms in some varieties of cheeses [hard cheese (Ras cheese), and processed cheese]. Material and Method: Thirty Ras cheese and processed cheese samples were collected randomly and subjected to chemical & microbiological examination to determine its contamination with deteriorating microorganisms. Results: Chemical examination showed that the mean titratable acidity % of Ras and Processed cheese samples were 0.5 ± 0.073 and 0.93% ± 0.062%, respectively, while salt % were 3.4 ± 0.078 and 1.03% ± 0.05%, respectively. Most of samples were contaminated with high numbers of Coliforms, yeast, mold, proteolytic, lipolytic and Enterococci. Conclusion: There are poor hygienic measures during production, processing and handling of cheese.

关键词： Titratable Acidity Salt proteolytic Microorganisms Coliforms Enterococci

Medium factors affecting extracellular protease activity by <i>Bacillus</i>sp. HTS 102—A novel wild strain isolated from Portuguese merino wool

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Natural Science 2013年第6期5卷 44-53页

作者： Ana Catarina Queiroga Manuela Estevez Pintado Francisco Xavier Malcata CBQF Porto Portugal Department of Chemical Engineering of University of Porto Porto Portugal

The synthesis of an extracellular protease by Bacillus sp. HTS102—a wild strain recently isolated from the wool of Portuguese Merino ewes, was optimized. This protease is thermostable and particularly resistant to harsh environmental conditions—and appears to bear a unique ability to hydrolyze keratin-rich solid materials. Following a preliminary screening for the most relevant medium factors involved in processing, a fractional factorial design (2VI6-1) was applied to ascertain the effects of six relevant parameters—viz. yeast extract concentration, peptone level, inoculum size, stirring rate, temperature and pH. The concentrations of yeast extract and peptone, as well as the incubation temperature and pH were found to play significant roles;and the 2-factor interaction between yeast extract level and pH was also significant. A 2.2-fold increase in the overall level of protease synthesis was eventually attained, with the improved medium relative to the basal medium—which is noteworthy when compared with competing proteases and previous optimization efforts.

关键词： Fractional Factorial Design Thermotolerant Enzyme proteolytic Activity Bacillus sp. Ewe’s Wool