The genetic basis of the biosynthesis of the germination-arrest factor (GAF) produced by Pseudomonas fluorescens WH6, and previously identified as 4-formylaminooxyvinylglycine, has been investigated here. In addition to inhibiting the germination of a wide range of grassy weeds, GAF exhibits a selective antimicrobial activity against the bacterial plant pathogen Erwinia amylovora. We utilized t...

In light of public concerns over the use of pesticides and antibiotics in plant protection and the subsequent selection for spread of resistant bacteria in the environment, it is inevitable to broaden our knowledge about viable alternatives, such as natural antagonists and their mode of action. The genus Pseudomonas is known for its metabolic versatility and genetic plasticity, encompassing pat...

Erwinia amylovora species were isolated from the blossoms, exudates, infected fruits, leaves and bent branches of diseased apple, pear and hawthorn trees, selected in the Chy, Osh and Jalal Abad regions. Biochemical and pathogenicity tests, alongside PCR analyses, were conducted to identify the local isolates of Erwinia amylovora. The alternative antagonistic microorganisms which combat bacteri...

This work describes a medium-based screening method for selecting microbial biocontrol agents against Erwinia amylovora based on the degradation of a specific growth factor. Erwinia amylovora, the causal agent of the devastating fire blight disease, requires nicotinic acid or nicotinamide as an essential growth factor. Potential biocontrol agents are either selected for antimicrobial production...

A 3.3 kb fragment from Erwinia amylovora phage Ea1h in plasmid pJH94 was previously characterized and found to contain an exopolysaccharide depolymerase (dpo) gene and two additional ORFs encoding 178 and 119 amino acids. ORF178 (lyz) and ORF119 (hol) were found to overlap by 19 bp and they resembled genes encoding lysozymes and holins. In nucleotide sequence alignments, lyz had structurally co...

rsmB(Ecc) specifies a nontranslatable RNA regulator that controls exoprotein production and pathogenicity in soft rot-causing Erwinia carotovora subsp. carotovora. This effect of rsmB(Ecc) RNA is mediated mostly by neutralizing the function of RsmA(Ecc), an RNA-binding protein of E. carotovora subsp. carotovora, which acts as a global negative regulator. To determine the occurrence of functiona...

The second messenger cyclic di-GMP (c-di-GMP) is a nearly ubiquitous intracellular signal molecule known to regulate various cellular processes, including biofilm formation, motility, and virulence. The intracellular concentration of c-di-GMP is inversely governed by diguanylate cyclase (DGC) enzymes and phosphodiesterase (PDE) enzymes, which synthesize and degrade c-di-GMP, respectively. The r...

The O-antigen gene clusters of Escherichia coli serogroups O117, O126, and O146 were sequenced, and 11, 10, and 11 open reading frames (ORFs) were identified, respectively. Genes required for O-antigen sugar biosynthesis, sugar transfer, and sugar processing were identified. Multiplex polymerase chain reaction (PCR) assays were developed targeting the wzx and wzy genes present in the O-antigen ...

fire blight, a bacterial disease caused by erwinia amylovora (burr.) winslow et al. 1920 is considered as a serious disease on pome fruits. during recent years, this disease has caused serious damages to the fruit growing industry in iran. precise and reliable methods for identification and detection of the pathogen can help in its early control, prevent the disease spread and help eliminate th...