scholarly journals Promoters maintain their relative activity levels under different growth conditions

2013 ◽  
Vol 9 (1) ◽  
pp. 701 ◽  
Author(s):  
Leeat Keren ◽  
Ora Zackay ◽  
Maya Lotan‐Pompan ◽  
Uri Barenholz ◽  
Erez Dekel ◽  
...  
Keyword(s):  
Growth Conditions ◽  
Relative Activity ◽  
Activity Levels

scholarly journals OPTIMIZATION OF BACTERIOCIN PRODUCTION BY Lactococcus lactis ssp. lactis CN1.10a ORIGIN FROM RUSIPS

2014 ◽  
Vol 9 (3) ◽  
pp. 97
Author(s):  
Ninoek Indriati ◽  
Arifah Kusmarwati ◽  
Irma Hermana
Keyword(s):  
Lactococcus Lactis ◽  
Growth Curve ◽  
Growth Conditions ◽  
Relative Activity ◽  
Bacteriocin Production ◽  
Bacteriocin Activity ◽  
Carbohydrate Source ◽  
Fermented Fish ◽  
Producer Cell

Previous study of bacteriocin production on laboratory scale (100 mL) that used MRS broth medium produced unstable activity of bacteriocin. Therefore, this study aims to determine the optimum growth conditions and media for production of bacteriocin. Bacteria used in this research was a lactic acid bacteria (LAB) Lactococcus lactis ssp. lactis CN1.10a  isolated from rusip, a traditional Bangkanese fermented fish product.The bacteria was first cultivated for subsequent use of bacteriocins production on intermediate scale (2L). Followed by the optimization of temperature, pH and medium for the bacteriocin production, determination of cell growth curve, bacteriocin production curve, bacteriocin activity on that scale, and also stability of bacteriocin during storage.The results showed that the optimum temperature and pH for the growth of producer cell were 28°C and pH 6. The greatest activity of bacteriocin was produced on CM medium (1% sucrose, 0,45% peptone, 1% yeast extract, 2,84% KH2PO4, 0,2% NaCl and 0,02% MgSO4.7H20) in addition of sucrose as carbohydrate source. Based on the growth curve performedon CM medium with KH2PO4, the L. Lactis ssp lactis CN1.10a was relatively stable up to 48 hours. Bacteriocin produced by the cell was  8000 AU/mlat24th hour.Bacteriocin  was relatively stable when stored at -20°C for 1month with a relative activity of 69,4%.

Concentration of bat activity in riparian habitats over an elevational gradient

1999 ◽  
Vol 77 (6) ◽  
pp. 972-977 ◽  
Author(s):  
S D Grindal ◽  
J L Morissette ◽  
R M Brigham
Keyword(s):  
Elevational Gradient ◽  
Relative Activity ◽  
Activity Levels ◽  
Riparian Areas ◽  
Habitat Types ◽  
Bat Activity ◽  
Prey Resources ◽  
Riparian Habitats ◽  
Mist Net ◽  
Capture Rates

Riparian areas are generally assumed to represent important foraging areas for insectivorous bats, but this contention has rarely been formally quantified. To test this assumption, we used bat detectors to compare the relative activity levels of a community of temperate-zone bat species between riparian (lake) and upland (cutblock) habitats at three different elevations (ranging from 540 to 1800 m) in a forested area of southern British Columbia. In addition, we also investigated the sex and age class distributions of bats (based on mist-net captures) between riparian and upland habitats among the elevational zones. Bat activity levels were significantly greater in riparian than upland areas (10 and 40 times greater for foraging and commuting activity, respectively). Capture rates were greater in riparian areas and biased towards females, suggesting that female bats may preferentially select riparian areas, probably because of the abundant prey resources typically associated with this habitat. Captures of females also predominated at lower elevations, whereas males were captured more often in higher elevation zones. Our data support the assumption that riparian habitats represent important foraging and probably drinking areas for bats. The sex bias and differences in capture rates and activity levels need to be considered when designing bat surveys in different habitat types or over elevational gradients.

Amygdala neuronal ensembles dynamically encode behavioral states

2018 ◽  
Author(s):  
Jan Gründemann ◽  
Yael Bitterman ◽  
Tingjia Lu ◽  
Sabine Krabbe ◽  
Benjamin F. Grewe ◽  
...  
Keyword(s):  
Internal State ◽  
Relative Activity ◽  
Activity Levels ◽  
Basal Nucleus ◽  
State Dependent ◽  
Internal States ◽  
Behavioral States ◽  
Sensory Responses ◽  
Motivated Behaviors ◽  
External Stimuli

AbstractInternal states, including affective or homeostatic states, are important behavioral motivators. The amygdala is a key brain region involved in the regulation of motivated behaviors, yet how distinct internal states are represented in amygdala circuits is unknown. Here, by imaging somatic neural calcium dynamics in freely moving mice, we identify changes in the relative activity levels of two major, non-overlapping populations of principal neurons in the basal nucleus of the amygdala (BA) that predict switches between exploratory and non-exploratory (defensive, anxiety-like) behavioral states across different environments. Moreover, the amygdala widely broadcasts internal state information via several output pathways to larger brain networks, and sensory responses in BA occur independently of behavioral state encoding. Thus, the brain processes external stimuli and internal states in an orthogonal manner, which may facilitate rapid and flexible selection of appropriate, state-dependent behavioral responses.

scholarly journals Differential Accumulation of Form I RubisCO in Rhodopseudomonas palustris CGA010 under Photoheterotrophic Growth Conditions with Reduced Carbon Sources

2009 ◽  
Vol 191 (13) ◽  
pp. 4243-4250 ◽  
Author(s):  
Gauri S. Joshi ◽  
Simona Romagnoli ◽  
Nathan C. VerBerkmoes ◽  
Robert L. Hettich ◽  
Dale Pelletier ◽  
...  
Keyword(s):  
Purple Bacteria ◽  
Rhodopseudomonas Palustris ◽  
Growth Conditions ◽  
Activity Levels ◽  
Two Component System ◽  
Rubisco Activity ◽  
Bisphosphate Carboxylase ◽  
Component System ◽  
Two Component ◽  
Photoheterotrophic Growth

ABSTRACT Rhodopseudomonas palustris is unique among characterized nonsulfur purple bacteria because of its capacity for anaerobic photoheterotrophic growth using aromatic acids. Like growth with other reduced electron donors, this growth typically requires the presence of bicarbonate/CO2 or some other added electron acceptor in the growth medium. Proteomic studies indicated that there was specific accumulation of form I ribulose 1, 5-bisphosphate carboxylase/oxygenase (RubisCO) subunit proteins (CbbL and CbbS), as well as the CbbX protein, in cells grown on benzoate without added bicarbonate; such cells used the small amounts of dissolved CO2 in the medium to support growth. These proteins were not observed in extracts from cells grown in the presence of high levels (10 mM) of added bicarbonate. To confirm the results of the proteomics studies, it was shown that the total RubisCO activity levels were significantly higher (five- to sevenfold higher) in wild-type (CGA010) cells grown on benzoate with a low level (0.5 mM) of added bicarbonate. Immunoblots indicated that the increase in RubisCO activity levels was due to a specific increase in the amount of form I RubisCO (CbbLS) and not in the amount of form II RubisCO (CbbM), which was constitutively expressed. Deletion of the main transcriptional regulator gene, cbbR, resulted in impaired growth on benzoate-containing low-bicarbonate media, and it was established that form I RubisCO synthesis was absolutely and specifically dependent on CbbR. To understand the regulatory role of the CbbRRS two-component system, strains with nonpolar deletions of the cbbRRS genes were grown on benzoate. Distinct from the results obtained with photoautotrophic growth conditions, the results of studies with various CbbRRS mutant strains indicated that this two-component system did not affect the observed enhanced synthesis of form I RubisCO under benzoate growth conditions. These studies indicate that diverse growth conditions differentially affect the ability of the CbbRRS two-component system to influence cbb transcription.

Amylase gene expression in intraspecific and interspecific somatic transformants of Drosophila

Genome ◽  
1990 ◽  
Vol 33 (4) ◽  
pp. 501-508 ◽  
Author(s):  
Sylvia A. Hawley ◽  
R. A. Norman ◽  
Celeste J. Brown ◽  
Winifred W. Doane ◽  
Wyatt W. Anderson ◽  
...  
Keyword(s):  
Functional Status ◽  
Transient Expression ◽  
Internal Control ◽  
Relative Activity ◽  
Activity Levels ◽  
Transient Expression Assay ◽  
Homologous Sequences ◽  
Electrophoretic Mobilities ◽  
Somatic Transformation ◽  
Amy Genes

The Amylase locus in Drosophila melanogaster normally contains two copies of the structural gene for α-amylase, a centromere-proximal copy, Amy-p, and a distal copy, Amy-d. Products of the two genes may display discrete electrophoretic mobilities, but many strains known to carry the Amy duplication are characterized by a single amylase electromorph, e.g., Oregon-R, which produces the mobility variant AMY-1. A transient expression assay was used in somatic transformation experiments to test the functional status of the Amy genes from an Oregon-R strain. Plasmid constructs containing either the proximal or distal copy were tested in amylase-null hosts. Both genes produced a functional AMY-1 isozyme. Constructs were tested against an AMY-3 reference activity produced by a coinjected plasmid that contains the Amy-d3 allele from a Canton-S strain. With reference to the internal control, the Amy-p and Amy-d genes from Oregon-R expressed different relative activity levels for AMY-1 in transient assays. The transient expression assay was successfully used to test the functional status of, Amy-homologous sequences from strains of other species of Drosophila characterized by a single amylase electromorph, namely, Drosophila pseudoobscura ST and Drosophila miranda S 204. The amylase-null strain of D. melanogaster provided the hosts for these interspecific somatic transformation experiments.Key words: α-amylase, Amy, transient assay, gene duplication, intergenic transformation.

Production of two bacteriocins in various growth conditions produced by gram-positive bacteria isolated from chicken cecum

2012 ◽  
Vol 58 (1) ◽  
pp. 93-101 ◽  
Author(s):  
Qiuju Wang ◽  
Yizhe Cui ◽  
Wenmei Wang ◽  
Jili Xu ◽  
Li Xu
Keyword(s):  
Nitrogen Sources ◽  
Antibacterial Activities ◽  
Growth Conditions ◽  
Proteinase K ◽  
Broiler Chicks ◽  
Activity Levels ◽  
Nutrient Sources ◽  
Gram Positive Bacteria ◽  
Physiological And Biochemical Characteristics ◽  
De Man

Lactobacillus plantarum CLP29 and Enterococcus faecium CLE34 isolated from the cecal contents of young broiler chicks were identified based on physiological and biochemical characteristics, and identification was confirmed by 16S rRNA sequencing. Both bacteria showed a broad range of inhibitory action against bacteria such as Salmonella and Escherichia coli and produced two peptides, plantaricin CLP29 and enterocin CLE34. Treatment with proteinase K, trypase, or benase resulted in the loss of activity of the two peptides, confirming their proteinaceous nature. The highest activity levels for both bacteria were recorded in de Man – Rogosa – Sharpe agar at pH 5.0, 6.0, and 7.0, at 37 °C. Carbon and nitrogen sources affected the antibacterial activities of the two bacteriocins in different combinations, which suggested that the antibacterial abilities of different bacteriocins produced in nutrient sources were various.

scholarly journals Neuronal congruency effects in macaque frontal cortex

2021 ◽  
Author(s):  
Tao Yao ◽  
Wim Vanduffel
Keyword(s):  
Selective Attention ◽  
Frontal Cortex ◽  
Congruency Effect ◽  
Irrelevant Stimulus ◽  
Relative Activity ◽  
Behavioral Performance ◽  
Activity Levels ◽  
Neuronal Mechanisms ◽  
Stimulus Features ◽  
Task Irrelevant

Abstract The interplay between task-relevant and task-irrelevant stimulus features induces conflicts which impair human behavioral performance in many perceptual and cognitive tasks, a.k.a. a behavioral congruency effect. The neuronal mechanisms underlying behavioral congruency effects, however, are poorly understood. We recorded single unit activity in monkey frontal cortex using a novel task-switching paradigm and discovered a neuronal congruency effect that is carried by task-relevant and -irrelevant neurons. The former neurons provide more signal, the latter less noise in congruent compared to incongruent conditions. Their relative activity levels determine the neuronal congruency effect and behavioral performance. Although these neuronal congruency signals are sensitive to selective attention, they cannot be entirely explained by selective attention as gauged by response time. We propose that such neuronal congruency effects can explain behavioral congruency effects in general, as well as previous fMRI and EEG results in various conflict paradigms.

scholarly journals Screening of bacterial strains for pectate lyase production and detection of optimal growth conditions for enhanced enzyme activity

2017 ◽  
Vol 9 (1) ◽  
pp. 370-374 ◽  
Author(s):  
Monidipta Saha ◽  
Rajib S. Rana ◽  
Biswanath Adhikary ◽  
Sabyasachi Mitra
Keyword(s):  
Enzyme Production ◽  
Pectate Lyase ◽  
Optimal Growth ◽  
Growth Conditions ◽  
Relative Activity ◽  
Subtilis Strain ◽  
Bacterial Strains ◽  
Apple Pectin ◽  
Citrus Pectin ◽  
Lyase Activity

In the present study, the pectatelyase production by fifty two bacterial strains isolated from ramie grown soils were studied and the strain RDSM01 showed maximum pectate lyase activity. According to sequence homology of Genbank, the strain RDSM01 was identified as Bacillus subtilis (Genbank Accession No. KX035109). Maximum pectate lyase activity of the strain was observed when 1.5% (v/v) inoculum was added to the growth medium and was incubated for 48 hours at 34-370C and at pH 7.0. The relative activity of the strain was 19% higher when apple pectin was used as carbon source compared to citrus pectin. Maximum enzyme production (149.1 – 153.4 IU/ml) was recorded when ammonium chloride or ammonium sulphate at 0.4% concentration was used as nitrogen source. Thus, B. subtilis strain RDSM01 possessing high pectate lyase activity may be effectively utilized for removal of gum from ramie fibre, which is primarily made of pectin and hemicellulose.

scholarly journals Gonadotropin-Releasing Hormone Modulates Vomeronasal Neuron Response to Male Salamander Pheromone

2012 ◽  
Vol 6 ◽  
pp. JEN.S8414 ◽  
Author(s):  
Celeste R. Wirsig-Wiechmann ◽  
Justin Colvard ◽  
Christopher E. Aston ◽  
Radhika Dighe ◽  
Lynne D. Houck ◽  
...  
Keyword(s):  
Relative Number ◽  
Relative Activity ◽  
Gonadotropin Releasing Hormone ◽  
Neural Activation ◽  
Activity Levels ◽  
Male Pheromone ◽  
Releasing Hormone ◽  
Relative Measure ◽  
Neuron Response ◽  
Electrophysiological Studies

Electrophysiological studies have shown that gonadotropin-releasing hormone (GnRH) modifies chemosensory neurons responses to odors. We have previously demonstrated that male Plethodon shermani pheromone stimulates vomeronasal neurons in the female conspecific. In the present study we used agmatine uptake as a relative measure of the effects of GnRH on this pheromone-induced neural activation of vomeronasal neurons. Whole male pheromone extract containing 3 millimolar agmatine with or without 10 micromolar GnRH was applied to the nasolabial groove of female salamanders for 45 minutes. Immunocytochemical procedures were conducted to visualize and quantify relative agmatine uptake as measured by labeling density of activated vomeronasal neurons. The relative number of labeled neurons did not differ between the two groups: pheromone alone or pheromone-GnRH. However, vomeronasal neurons exposed to pheromone-GnRH collectively demonstrated higher labeling intensity, as a percentage above background (75%) as compared with neurons exposed to pheromone alone (63%, P < 0.018). Since the labeling intensity of agmatine within neurons signifies the relative activity levels of the neurons, these results suggest that GnRH increases the response of female vomeronasal neurons to male pheromone.

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