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A comparative analysis of entomoparasitic nematodes <i>Heterorhabditis bacteriophora</i>and <i>Steinernema carpocapsae</i>

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Open Journal of Animal Sciences 2013年第4期3卷 326-333页

作者： Rinu Kooliyottil Devang Upadhyay Floyd Inman III Sivanadane Mandjiny Len Holmes sartorius stedim biotechnology laboratory Biotechnology Research and Training Center University of North Carolina at Pembroke Pembroke USA sartorius stedim biotechnology laboratory Biotechnology Research and Training Center University of North Carolina at Pembroke Pembroke USA

Heterorhabditis bacteriophora and Steinernema carpocapsae are microscopic entomoparasitic nematodes (EPNs) that are attractive, organic alternatives for controlling a wide range of crop insect pests. EPNs evolved with parasitic adaptations that enable them to “feast” upon insect hosts. The infective juvenile, a non-feeding, developmentally arrested nematode stage, is destined to seek out insect hosts and initiates parasitism. After an insect host is located, EPNs enter the insect body through natural openings or by cuticle penetration. Upon access to the insect hemolymph, bacterial symbionts (Photorhabdus luminescens for H. bacteriophora and Xenorhabdus nematophila for S. carpocapsae) are regurgitated from the nematode gut and rapidly proliferate. During population growth, bacterial symbionts secrete numerous toxins and degradative enzymes that exterminate and bioconvert the host insect. During development and reproduction, EPNs obtain their nutrition by feeding upon both the bioconverted host and proliferated symbiont. Throughout the EPN life cycle, similar characteristics are seen. In general, EPNs are analogous to each other by the fact that their life cycle consists of five stages of development. Furthermore, reproduction is much more complex and varies between genera and species. In other words, infective juveniles of S. carpocapsae are destined to become males and females, whereas H. bacteriophora develop into hermaphrodites that produce subsequent generations of males and females. Other differences include insect host range, population growth rates, specificity of bacterial phase variants, etc. This review attempts to compare EPNs, their bacterial counterparts and symbiotic relationships for further enhancement of mass producing EPNs in liquid media.

关键词： Entomoparasitic Nematodes (EPNs) Heterorhabditis Bacteriophora Steinernema Carpocapsae Photorhabdus Luminescens Xenorhabdus Nematophila Symbiosis Mass Production

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The Effects of Trehalose on the Bioluminescence and Pigmentation of the Phase I Variant of Photorhabdus luminescens

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Journal of Life Sciences 2012年第2期6卷 119-129页

作者： Floyd L. Inman III Leonard D. Holmes sartorius-stedim biotechnology laboratory Biotechnology Research and Training Center University of North Carolina PembrokeNC 28372 USA

Photorhabdus luminescens is a Gram-negative, bioluminescent, pigment producing enteric bacterium, which is pathogenic to insects and has the capability to undergo phase variation. The phase I variant of P. luminescens exists as a mutualistic symbiont where it plays a critical role in the life-cycle of the soil-dwelling nematode, Heterorhabditis bacteriophora. Both the bacterium and the nematode receive their nutritional requirements from the bioconversion of the insect host which is rich in many macromolecules such as the disaccharide, trehalose. Trehalose is a non-reducing disaccharide of glucose that is formed by an a-1,1-glycosidic bond and is associated with the physiology of many bacteria, insects and nematodes. Trehalose has been shown to be the most abundant storage sugar found within insect hemolymph （1%-2%）. The physicochemical properties of trehalose allow this carbohydrate to act as a stress protectant where it has been implicated with thermal stress, dehydration, and osmotic protection of many microorganisms. Due to these properties, trehalose may allow culture stability of the phase I variant in vitro and in vivo. Traits of the phase I variant that were studied in this work include bioluminescence and the production of the red anthroquinone-derived pigment. The carbohydrates that were utilized in this study were glucose and trehalose; where shake flask cultures of the phase I variant were cultured at room temperature for up to six days in carbohydrate supplemented basal media with increasing carbohydrate concentrations of 0. 1%, 0.5% and 1.0% （v/v）. Relative luminosity, pigmentation and pH were graphed as a function of time, carbohydrate used, and carbohydrate concentration. Data obtained from this study suggests that the supplementation of 1.0% trehalose, when culturing the phase I variant ofP. luminescens, can maintain bioluminosity and pigmentation over extended periods of time （five days） as compared to basal media and basal media supplemented with

关键词： Trehalose Photorhabdus luminescens pigmentation bioluminescence Heterorhabditis bacteriophora.

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A Novel Method for Determining Microbial Kinetics

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Journal of Life Sciences 2013年第8期7卷 787-790页

作者： Anne M. Talkington Floyd L. Inman III Leonard D. Holmes sartorius stedim-biotechnology laboratory Biotechnology Research and Training Center University of North Carolina atPembroke Pembroke North Carolina 28372 USA

Understanding microbial growth is essential to any research conducted in the fields of microbiology and biotechnology. Current methods of determining growth characteristics of microbes involve subjective graphical interpretations of linearized logarithmic data. Reducing error in logistical data decreases disparity between graphical and analytical predictions of microbial characteristics. In this study, a method has been developed to calculate the kinetics of microbial characteristics utilizing a modified Maclaurin series. Convergence of this series approaches the true kinetic value of microbial characteristics to include specific growth rates. In this research, a modified Maclaurin series is used to evaluate microbial kinetics in comparison to graphical determinations.

关键词： Microbial kinetics Maclaurin series microbial growth models series convergence.

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1,n-Thiosulfonylation using thiosulfonates as dual functional reagents

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Chinese Chemical Letters 2022年第11期33卷 4732-4739页

作者： Danhua Ge Jia-Wei Chen Pei Xu Jinyin Pan Xue-Qiang Chu Institute of Advanced Synthesis School of Chemistry and Molecular EngineeringNanjing Tech UniversityNanjing 211816China Jiangsu Key laboratory of New Drug Research and Clinical Pharmacy School of PharmacyXuzhou Medical UniversityXuzhou 221004China sartorius stedim(Shanghai)Trading Co. Ltd.Shanghai 200000China

In recent years,the direct introduction of sulfonyl and sulfenyl groups into unsaturated substrates by using thiosulfonates as unique dual functional reagents has inarguably provided chemists a new platform for the diverse synthesis of important S-containing *** 1,n-thiosulfonylation reactions usually feature simple procedures,100%atom economy,and high *** review focuses on the recent advancements in the transformations of thiosulfonates through 1,n-thiosulfonylation involving the formation of two distinct C-S bonds under transition-metal-catalyzed or metal-free conditions,where thiosulfonates act as both a sulfonyl and a sulfenyl component.

关键词： Thiosulfonylation Thiosulfonates Dual functional reagents Difunctionalization Atomic economy

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A Deleted Deletion Site in a New Vector Strain and Exceptional Genomic Stability of Plaque-Purified Modified Vaccinia Ankara(MVA)

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Virologica Sinica 2020年第2期35卷 212-226页

作者： Ingo Jordan Deborah Horn Kristin Thiele Lars Haag Katharina Fiddeke Volker Sandig ProBioGen AG.Herbert-Bayer-StraBe 8 13086 BerlinGermany sartorius stedim Cellca GmbH.Erwin-Rentschler-Str 21 88471 LaupheimGermany Vironova AB Giivlegatan 2211330 StockholmSweden Department of laboratory Medicine Karolinska Universitetsjukhuset i Huddinge14152 HuddingeSweden

Vectored vaccines based on highly attenuated modified vaccinia Ankara(MVA) are reported to be immunogenic, tolerant to pre-existing immunity, and able to accommodate and stably maintain very large transgenes. MVA is usually produced on primary chicken embryo fibroblasts, but production processes based on continuous cell lines emerge as increasingly robust and cost-effective alternatives. An isolate of a hitherto undescribed genotype was recovered by passage of a nonplaque-purified preparation of MVA in a continuous anatine suspension cell line(***) in chemically defined *** novel isolate(MVA-CR19) replicated to higher infectious titers in the extracellular volume of suspension cultures and induced fewer syncytia in adherent cultures. We now extend previous studies with the investigation of the point mutations in structural genes of MVA-CR19 and describe an additional point mutation in a regulatory gene. We furthermore map and discuss an extensive rearrangement of the left telomer of MVA-CR19 that appears to have occurred by duplication of the right telomer. This event caused deletions and duplications of genes that may modulate immunologic properties of MVACR19 as a vaccine vector. Our characterizations also highlight the exceptional genetic stability of plaque-purified MVA:although the phenotype of MVA-CR19 appears to be advantageous for replication, we found that all genetic markers that differentiate wildtype and MVA-CR19 are stably maintained in passages of recombinant viruses based on either wildtype or MVA-CR.

关键词： Modified vaccinia Ankara(MVA) MVA-CR19 CR.pIX Suspension cell line Vaccine production Genome stability

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Bioluminescence and Chitinase Production during Chitin Fermentation by Vibrio harveyi

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Journal of Life Sciences 2013年第5期7卷 491-494页

作者： Badireddy Madhusudana Rao Floyd L. Inman Ⅲ Leonard D. Holmes sartorius stedim biotechnology laboratory Biotechnology Research and Training Center University of North Carolina NorthCarolina 28472 USA Central Institute of Fisheries Technology Visakhapatnam Research Centre Andhra University Visakhapatnam 530003 India

Vibrio harveyi, like other luminescent bacteria, is capable of producing extracellular chitinases. Microbial chitinases are utilized to depolymerize chitin into chitooligosaccharides and N-acetylglucosamine for the acquisition of carbon and possibly nitrogen, needed for survival. For many luminous marine bacteria （Vibrio spp.）, quorum-sensing is highly speculated to be responsible for bioluminescence; however, in terrestrial species （Photorhabdus spp.） luminosity seems to be controlled through unknown mechanism of phase variation. In the present work, the correlation between bacterial luminosity and chitinase production of F. harveyi was studied. The utilization of bioluminescence could prove to be an easier and more convenient method to monitor chitin fermentations that employ luminous bacteria. Results from the fermentation study indicate that luminosity of F. harveyi inversely correlates with chitinase production. In other words, during chitin fermentation, chitinase production was seen to increase while luminosity decreased with respect to growth and growth conditions. Furthermore, the results also suggest that V. harveyi may utilize an alternate mechanism that can counter quorum-sensing mechanisms to ensure bacterial survival under deteriorating growth conditions. The inverse relationship observed in this study may lead to a basic understanding of monitoring and studying chitin fermentations and anti-quorum-sensing/phase variation mechanisms exhibited by luminous bacteria.

关键词： Vibrio harveyi bioluminescence chitinase chitin fermentation.

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Seasonal variation in body mass and energy budget in Chinese bulbuls (pycnonotus sinensis)

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Chinese Birds 2014年第1期5卷 21-30页

作者： Mengsi Wu Yuchao Xiao Fang Yang Limeng Zhou Weihong Zheng Jinsong Liu School of Life and Environmental Sciences Wenzhou University Key laboratory for Subtropical Water Environment and Marine Biological Resources Protection in Zhejiang Province

Background: Seasonal adjustments in body mass and energy budget are important for the survival of small birds in temperate zones. Seasonal changes in body mass, body temperature, gross energy intake(GEI), digestible energy intake(DEI), body fat content, as well as length and mass of the digestive tract, were measured in Chinese Bulbuls(Pycnonotus sinensis) caught in the wild at Wenzhou, ***: Body mass was determined with a sartorius balance. The caloric contents of the dried food and feces were then determined using a oxygen bomb calorimeter. Total fat was extracted from the dried carcasses by ether extraction in a Soxhlet apparatus. The digestive tract of each bird was measured and weighed, and was then dried to a constant ***: Body mass showed a significant seasonal variation and was higher in spring and winter than in summer and autumn. Body fat was higher in winter than in other seasons. GEI and DEI were significantly higher in *** length and mass of the digestive tract were greatest in winter and the magnitude of both these parameters was positively correlated with body mass, GEI and DEI. Small passerines typically have higher daily energy expenditure in winter, necessitating increased food ***: This general observation is consistent with the observed winter increase in gut volume and body mass in Chinese Bulbuls. These results suggest that Chinese Bulbuls adjust to winter conditions by increasing their body mass, body fat, GEI, DEI and digestive tract size.

关键词： Digestive tract Energy budget Morphology Pycnonotus sinensis Seasonal variation

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Daily variation in body mass and thermoregulation in male Hwamei(Garrulax canorus) at different seasons

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Chinese Birds 2015年第1期6卷 14-21页

作者： Lidan Zhao Runmei Wang Yunan Wu Mengsi Wu Weihong Zheng Jinsong Liu School of Life and Environmental Sciences Wenzhou University Key laboratory of Water Environment and Marine Biological Resources Protection in Zhejiang Province Wenzhou University

Background: Acclimatization to winter conditions is an essential prerequisite for survival of small passerines of the northern temperate zone. In the present study, we measured diurnal variations in body mass, body temperature and basal metabolic rate(BMR) for seasonally acclimatized Hwameis(Garrulax canorus).Methods: Body mass was determined with a sartorius balance. Metabolic rates of Hwameis were measured with an open-circuit respirometry ***: Body masses varied with time of day and were higher in daytime for Hwameis in both summer and winter, and body masses in winter were higher compared to that in summer. Body temperatures of Hwameis were higher in daytime, and the summer acclimatized birds had significantly higher body temperatures compared to the winter acclimatized birds. BMRs of Hwameis were significantly higher during the daytime compared to the nighttime of the daily cycle in both summer and winter, and Hwameis in winter had significantly higher BMRs than that in ***: This result showed that Hwameis rely mostly on metabolic capacity to maintain their body temperature in cold weathers, and Hwameis exhibited daily and seasonal flexibility in morphology and physiology which is important under changing environmental conditions.

关键词： Hwamei(Garrulax canorus) Body mass Body temperature Diurnal rhythm Metabolic rate

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Remote Control of Fed-Batch Fermentation Systems

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Journal of Chemistry and Chemical Engineering 2011年第10期5卷 897-902页

作者： Eric Moreau Floyd Inman, III Sunita Singh Heather Walters Leonard Holmes biotechnology Research and Training Center University of North Carolina at Pembroke Pembroke NC USA Central Institute of Agricultural Engineering Bhopal Madhya Pradesh India Universite de Picardie Jules Verne Amiens France

Bioreactor operation requires continuous monitoring of fermentation parameters and real-time control over bioreactor devices. Remote monitoring and control of the bioreactor＇s computer via the Internet avoids the necessity of personnel being continually onsite during operation. A two liter sartorius-stedim Biostat~ A Plus fermentation system was networked and interfaced with the commercial software from GoToMyPC to allow remote control of the fermentation system utilizing the internet. The fermentation vessel was equipped with hardware calibrated for monitoring and controlling culture parameters during experimentations. The uniform resource locator controlled night-vision web camera allowed continuous monitoring of the glass fermentation vessel during the day and at night. The main window screen of the laboratory computer can be securely accessed from any portable device （i.e. laptop） capable of establishing an Internet connection and executing the commercial software from GoToMyPC. The secured internet protocol address, provided by GoToMyPC, assures that the system can only be controlled by authorized users who have been given access to the account. This interface permits the remote control of the Biostat A Plus fermentation system and possibly other automated or potentially automated culturing systems at the convenience of the user（s）.

关键词： Fermentation Fed-batch Remote-monitoring Remote-controlled fermentation systems

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Potential sources and health risk of polycyclic aromatic hydrocarbons in PM2.5 at a national background site in North China

Potential sources and health risk of polycyclic aromatic hyd...

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第十八届中国科协年会——分12 大气雾霾及PM2.5控制先进技术研讨会

作者： Xiaoping WANG Chongguo TIAN Yingjun CHEN Zheng ZONG Jun LI Gan ZHANG State Key laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Key laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone Research Chinese Academy of Sciences Key laboratory of Cities' Mitigation and Adaptation to Climate Change in Shanghai College of Environmental Science and Engineering Tongji University

Air quality in Northern China is notoriously poor and recently has become an issue associated with increasing social unrest. To examine the regional pollution patterns, a PM(aerosol particle with aerodynamic diameter less than 2.5 μm) sampling campaign was conducted to analyze the concentration and composition of polycyclic aromatic hydrocarbons(PAHs) at a national station for background atmospheric monitoring(38.19 oN, 120.74oE) of the Tuoji Island(TI), China. A total of 75 PM samples were collected on quartz fiber filters from November 2011 to January 2013(Whatman, QM-A, 20.3×25.4 cm) using a high volume sampler at a flow rate of 1.1 m min. Sampled filters were analyzed gravimetrically for mass concentrations of PM using a sartorius MC5 electronic microbalance. After measurement of mass concentrations, the sampled filter was punched for specific size(1punch φd=47mm) and exacted 24 h with soxhlet extractor method for the PAHs analysis. Concentrations of 16 USEPA priority PAHs(ΣPAHs) were determined with a gas chromatography-mass spectrometry(GC-MS) device(Agilent GC6890/MSD 5973). The results showed that the mean of PM concentrations was 53.5 μg m, ranged from 7.8 to 144.2 μg m during the sampling period. On the season, the lowest values were in winter of 2011 and the highest in spring of 2012. The total concentration of Σ16PAHs ranged from 4.7 to 41 ng m, with an average value of 17±10 ng m, and high PAHs concentrations occurred in cold seasons while low concentrations in warm seasons. An integrated approach of air mass back trajectories, molecular tracers, isomer ratios of PAHs and potential source contribution function analysis was used to identify potential sources. It is shown that biomass burning in Shandong Peninsula during summer is the main PAH source while the outflow of coal combustion and mixed emissions from Jing-Jin-Ji and adjacent areas contributes a high PAH level in cold season. The total toxic uivalent of PAHs(Ba P) at this site ranges from 0.54 t

关键词： PM2.5 PAHs Tuoji Island source identification health risk

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