Diversity of the type VI secretion systems in the spp.

Complete Type VI Secretion Systems were identified in the genome sequence data of isolates sourced from throat swabs of human volunteers. The previous report was the first to describe two complete Type VI Secretion Systems in these isolates, both of which were distinct in terms of their gene organization and sequence homology. Since publication of the first report, Type VI Secretion System subtypes have been identified in spp.

Bacterial Adaptation to Venom in Snakes and Arachnida.

Animal venoms are considered sterile sources of antimicrobial compounds with strong membrane-disrupting activity against multidrug-resistant bacteria. However, venomous bite wound infections are common in developing nations. Investigating the envenomation organ and venom microbiota of five snake and two spider species, we observed venom community structures that depend on the host venomous animal species and evidenced recovery of viable microorganisms from black-necked spitting cobra (Naja nigricollis) and Indian ornamental tarantula (Poecilotheria regalis) venoms.

The safety profile of Bald's eyesalve for the treatment of bacterial infections.

The rise in antimicrobial resistance has prompted the development of alternatives to combat bacterial infections. Bald's eyesalve, a remedy used in the Early Medieval period, has previously been shown to have efficacy against Staphylococcus aureus in in vitro and in vivo models of chronic wounds. However, the safety profile of Bald's eyesalve has not yet been demonstrated, and this is vital before testing in humans.

Virulence genes and previously unexplored gene clusters in four commensal spp. isolated from the human throat expand the neisserial gene repertoire.

Commensal non-pathogenic spp. live within the human host alongside the pathogenic and and due to natural competence, horizontal gene transfer within the genus is possible and has been observed. Four distinct spp.

Monocaprin eye drop formulation to combat antibiotic resistant gonococcal blindness.

Neisseria gonorrhoeae bacteria are acknowledged as an urgent threat to human health because this species has developed resistances to all of the antibiotics used clinically to treat its infections. N. gonorrhoeae causes the sexually transmitted disease gonorrhoea, but also causes blindness when the bacteria infect the eyes.

In Vitro Models of Eye Infection with Neisseria gonorrhoeae.

Prophylaxis with silver nitrate and later antibiotics has significantly reduced the cases of infant blindness from gonococcal infection at birth to the point where it has all but been forgotten in the developed world as the devastating disease that it was in the pre-antibiotic era. As a result, while it is known that the bacteria are transmitted to the eyes during passage through the infected birth canal, little is known about Neisseria gonorrhoeae colonization of the eye and the establishment and progression of keratitis. Treatment failures due to rising antimicrobial resistance necessitate investigations into all aspects of gonococcal disease, including eye infections, so that new treatment strategies can be developed.

The Growing Threat of Gonococcal Blindness.

Antibiotic-resistant gonorrhea is now a reality, as well as the consequences of untreatable infections. Gonococcal eye infections result in blindness if not properly treated; they accounted for the vast majority of infections in children in homes for the blind in the pre-antibiotic era. infects the eyes of infants born to mothers with gonorrhea and can also infect the eyes of adults.

Alternative antimicrobials: the properties of fatty acids and monoglycerides.

With the rising antibiotic resistance of many bacterial species, alternative treatments are necessary to combat infectious diseases. The World Health Organization and the US Centres for Disease Control and Prevention have warned that some infections, such as those from Neisseria gonorrhoeae, may be untreatable within a few years. One avenue of exploration is the use of antimicrobial fatty acids and their derivatives for therapeutic prevention or treatment of bacterial infections.

Mutations in Neisseria gonorrhoeae grown in sub-lethal concentrations of monocaprin do not confer resistance.

Neisseria gonorrhoeae, due to its short lipooligosaccharide structure, is generally more sensitive to the antimicrobial effects of some fatty acids than most other Gram negative bacteria. This supports recent development of a fatty acid-based potential treatment for gonococcal infections, particularly ophthalmia neonatorum. The N.

Investigating Potential Chromosomal Rearrangements during Laboratory Culture of Neisseria gonorrhoeae.

Comparisons of genome sequence data between different strains and isolates of spp., such as , reveal that over the evolutionary history of these organisms, large scale chromosomal rearrangements have occurred. Factors within the genomes, such as repetitive sequences and prophage, are believed to have contributed to these observations.

Fatty Acid Based Microemulsions to Combat Ophthalmia Neonatorum Caused by Neisseria gonorrhoeae and Staphylococcus aureus.

The bacterial species () and () are amongst the main microorganisms that cause ophthalmia neonatorum. The current treatment involves the use of various antibiotics such as ciprofloxacin, cephalosporin, ceftriaxone and cefotaxime. However, this treatment strategy is becoming more ineffective due to the antibiotic resistance in The current study explores the potential use of fatty acid based microemulsions (ME) to prevent and infections in new-borns' eyes without harmful side effects such as corneal or conjunctiva irritation.

Phase variable DNA repeats in influence transcription, translation, and protein sequence variation.

There are many types of repeated DNA sequences in the genomes of the species of the genus , from homopolymeric tracts to tandem repeats of hundreds of bases. Some of these have roles in the phase-variable expression of genes. When a repeat mediates phase variation, reversible switching between tract lengths occurs, which in the species of the genus most often causes the gene to switch between on and off states through frame shifting of the open reading frame.

DNA uptake sequences in as intrinsic transcriptional terminators and markers of horizontal gene transfer.

DNA uptake sequences are widespread throughout the genome. These short, conserved sequences facilitate the exchange of endogenous DNA between members of the genus . Often the DNA uptake sequences are present as inverted repeats that are able to form hairpin structures.

Inversion of Correia repeat enclosed elements in .

is capable of causing gonorrhoea and more complex diseases in the human host. Within the gonococcal genome are over 100 copies of the insertion sequence-like Correia repeat enclosed element (CREE), which has been predicted to be mobile within the neisserial genomes. Although there is evidence of ancestral movement of these elements, no previous study has provided evidence for current mobilization.

Fatty acid microemulsion for the treatment of neonatal conjunctivitis: quantification, characterisation and evaluation of antimicrobial activity.

Fatty acids (FAs) are used by many organisms as defence mechanism against virulent bacteria. The high safety profile and broad spectrum of activity make them potential alternatives to currently used topical antibiotics for the treatment of eye infections in neonates. The current study utilised a Design of Experiment approach to optimise the quantification of five fatty acids namely; lauric acid, tridecanoic acid, myristoleic acid, palmitoleic acid and α-linolenic acid.

Correia Repeat Enclosed Elements and Non-Coding RNAs in the Neisseria Species.

Neisseria gonorrhoeae is capable of causing gonorrhoea and more complex diseases in the human host. Neisseria meningitidis is a closely related pathogen that shares many of the same genomic features and virulence factors, but causes the life threatening diseases meningococcal meningitis and septicaemia. The importance of non-coding RNAs in gene regulation has become increasingly evident having been demonstrated to be involved in regulons responsible for iron acquisition, antigenic variation, and virulence.

Insight into proteomic investigations of Neisseria meningitidis serogroup C strain L91543 from analysis of its genome sequence.

Here, we describe the draft sequence of a virulent isolate of Neisseria meningitidis strain L91543, belonging to serogroup C. The findings from previous proteomic and metabolomic studies of this strain can now be further interpreted with genomic analysis. Comparative analysis of the genome sequence revealed close similarity and localized synteny with the genome sequence of N.

Microarray analysis of the Ler regulon in enteropathogenic and enterohaemorrhagic Escherichia coli strains.

The type III protein secretion system is an important pathogenicity factor of enteropathogenic and enterohaemorrhagic Escherichia coli pathotypes. The genes encoding this apparatus are located on a pathogenicity island (the locus of enterocyte effacement) and are transcriptionally activated by the master regulator Ler. In each pathotype Ler is also known to regulate genes located elsewhere on the chromosome, but the full extent of the Ler regulon is unclear, especially for enteropathogenic E.

Sequence features contributing to chromosomal rearrangements in Neisseria gonorrhoeae.

Through whole genome sequence alignments, breakpoints in chromosomal synteny can be identified and the sequence features associated with these determined. Alignments of the genome sequences of Neisseria gonorrhoeae strain FA1090, N.gonorrhoeae strain NCCP11945, and N.

Simple sequence repeats in Helicobacter canadensis and their role in phase variable expression and C-terminal sequence switching.

Background: Helicobacter canadensis is an emerging human pathogen and zoonotic agent. The genome of H. canadensis was sequenced previously and determined to contain 29 annotated coding regions associated with homopolymeric tracts.

The complete genome and proteome of Laribacter hongkongensis reveal potential mechanisms for adaptations to different temperatures and habitats.

Laribacter hongkongensis is a newly discovered Gram-negative bacillus of the Neisseriaceae family associated with freshwater fish-borne gastroenteritis and traveler's diarrhea. The complete genome sequence of L. hongkongensis HLHK9, recovered from an immunocompetent patient with severe gastroenteritis, consists of a 3,169-kb chromosome with G+C content of 62.

Comparative analysis of two Neisseria gonorrhoeae genome sequences reveals evidence of mobilization of Correia Repeat Enclosed Elements and their role in regulation.

Background: The Correia Repeat Enclosed Element (CREE) of the Neisseria spp., with its inverted repeat and conserved core structure, can generate a promoter sequence at either or both ends, can bind IHF, and can bind RNase III and either be cleaved by it or protected by it. As such, the presence of this element can directly control the expression of adjacent genes.

Bacterial flagellar diversity and evolution: seek simplicity and distrust it?

Flagella are the chief organelles of motility in bacteria. In recent years, several new findings have illuminated the evolution of bacterial flagella, including cut-down versions of the organelle in Buchnera, a dispensable ATPase and structural evidence for homology between FliG (a component of the flagellar motor) and MgtE (a magnesium transporter). However, a fresh examination of the phylogenetic distribution of flagellar genes warns against a simplistic model of early flagellar evolution.