scholarly journals Identification and Characterization of theErwinia amylovora rpoS Gene: RpoS Is Not Involved in Induction of Fireblight Disease Symptoms

1998 ◽  
Vol 180 (24) ◽  
pp. 6789-6792 ◽  
Author(s):  
M. Anderson ◽  
C. E. Pollitt ◽  
I. S. Roberts ◽  
J. A. Eastgate

ABSTRACT The Erwinia amylovora rpoS gene, encoding the alternative sigma factor RpoS, has been cloned and characterized. Though highly sensitive to a number of environmental stresses, anE. amylovora rpoS mutant was not compromised in its ability to grow or cause disease symptoms within apple seedlings or in an overwintering model.

Gene ◽  
2006 ◽  
Vol 376 (1) ◽  
pp. 144-151 ◽  
Author(s):  
Zakee L. Sabree ◽  
Veit Bergendahl ◽  
Mark R. Liles ◽  
Richard R. Burgess ◽  
Robert M. Goodman ◽  
...  

2009 ◽  
Vol 2009 ◽  
pp. 1-9 ◽  
Author(s):  
Jing-jing Zhao ◽  
Chang Chen ◽  
Lv-ping Zhang ◽  
Chao-qun Hu

Vibrio alginolyticusZJ-51 displays phase variation between opaque/rugose colonies (Op) and translucent/smooth colonies (Tr). These colony variants show great differences in biofilm formation and motility. In this study, a gene encoding for anrpoS-like sigma factor,rpoX, has been cloned and characterized. The absence ofrpoXdid not affect colony switching rate but did decrease biofilm formation in both the Op and the Tr variants. When challenged with hydrogen peroxide, theΔrpoXin the Op background showed a slightly higher survival rate compared with the wild type, whereas survival was decreased in the Tr background. Deletion ofrpoXin the Tr background resulted in a higher ability to resist ethanol challenges and to survive hyperosmolarity challenges, and in the Op background the opposite phenotype was observed. This indicates that therpoXgene is involved in biofilm formation and stress response but the effects are controlled by colony phase variation inV. alginolyticus.


2021 ◽  
Vol 22 (11) ◽  
pp. 6148
Author(s):  
Matteo Miceli ◽  
Silvana Casati ◽  
Pietro Allevi ◽  
Silvia Berra ◽  
Roberta Ottria ◽  
...  

A novel bioluminescent Monoacylglycerol lipase (MAGL) substrate 6-O-arachidonoylluciferin, a D-luciferin derivative, was synthesized, physico-chemically characterized, and used as highly sensitive substrate for MAGL in an assay developed for this purpose. We present here a new method based on the enzymatic cleavage of arachidonic acid with luciferin release using human Monoacylglycerol lipase (hMAGL) followed by its reaction with a chimeric luciferase, PLG2, to produce bioluminescence. Enzymatic cleavage of the new substrate by MAGL was demonstrated, and kinetic constants Km and Vmax were determined. 6-O-arachidonoylluciferin has proved to be a highly sensitive substrate for MAGL. The bioluminescence assay (LOD 90 pM, LOQ 300 pM) is much more sensitive and should suffer fewer biological interferences in cells lysate applications than typical fluorometric methods. The assay was validated for the identification and characterization of MAGL modulators using the well-known MAGL inhibitor JZL184. The use of PLG2 displaying distinct bioluminescence color and kinetics may offer a highly desirable opportunity to extend the range of applications to cell-based assays.


FEBS Letters ◽  
1999 ◽  
Vol 455 (1-2) ◽  
pp. 13-17 ◽  
Author(s):  
Monica Emanuelli ◽  
Francesco Carnevali ◽  
Maria Lorenzi ◽  
Nadia Raffaelli ◽  
Adolfo Amici ◽  
...  

1998 ◽  
Vol 72 (5) ◽  
pp. 3507-3511 ◽  
Author(s):  
A. Kroneman ◽  
L. A. H. M. Cornelissen ◽  
M. C. Horzinek ◽  
R. J. de Groot ◽  
H. F. Egberink

ABSTRACT A porcine torovirus (PoTV) was identified and characterized; it is a novel member of the genus Torovirus (familyCoronaviridae, order Nidovirales), closely related to but clearly distinct from the already recognized equine torovirus (ETV) and bovine torovirus (BoTV) representatives. Immunoelectron microscopy of feces from piglets revealed elongated, 120- by 55-nm particles which were recognized by a torovirus-specific antiserum. Amplification by reverse transcriptase (RT) PCR with primers designed to detect conserved regions (on the basis of the genomes of BoTV strain Breda and ETV strain Berne) resulted in the identification of the 489-bp nucleocapsid gene, encoding a 18.7-kDa protein. The sequence identity in this region between PoTV and both ETV and BoTV was only about 68%, whereas the latter two show 81% identity. Neutralizing antibodies directed against ETV were found in sera of adult and young pigs. In all 10 herds sampled, seropositive animals were present, and 81% of randomly selected adult sows possessed antibodies. A longitudinal study with RT PCR showed that piglets shed virus in the feces for 1 or more days, starting 4 to 14 days after weaning.


Sign in / Sign up

Export Citation Format

Share Document