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Background: Antenatal screening is vital to identifying couples at risk of having children with a clinically significant haemoglobinopathy. In Australia, immigration is increasing carrier incidence. Methods: A retrospective analysis was performed of full blood count, high-performance liquid chromatography and haemoglobin electrophoresis of women and their partners who underwent antenatal haemoglobinopathy screening over three years at a major NSW laboratory. Genetic testing results were included where available. Results: One thousand six hundred and twenty-eight women and 729 male partners were screened at a median gestation of 14 weeks. 8.2% of women had a clinically significant result, with a median 16-day interval to partner testing. In 35% of couples screened simultaneously, the partner did not require testing. Genetic confirmatory testing was performed in 65% of high risk couples. Conclusion: There was a significant delay to antenatal haemoglobinopathy screening for mothers, limiting time for genetic diagnosis, prenatal diagnosis and management of affected pregnancies. Screening should be performed earlier. Simultaneous couple testing is not cost-effective. [ABSTRACT FROM AUTHOR]

A lectin detected in haemolymph from the Australian spiny lobster Panulirus cygnus agglutinated human ABO Group A cells to a higher titre than Group O or B. The lectin also agglutinated rat and sheep erythrocytes, with reactivity with rat erythrocytes strongly enhanced by treatment with the proteolytic enzyme papain, an observation consistent with reactivity via a glycolipid. The lectin, purified by affinity chromatography on fixed rat-erythrocyte stroma, was inhibited equally by N-acetylglucosamine and N-acetylgalactosamine. Comparison of data from gel filtration of haemolymph (behaving as a 1,800,000 Da macromolecule), and polyacrylamide gel electrophoresis of purified lectin (a single 67,000 Da band), suggested that in haemolymph the lecin was amultimer. The purified anti-A lectin autoprecipitated unless the storage solution contained chaotropic inhibitors (125 mmol/L sucrose: 500 mmol/L urea). The properties of this anti-A lectin and other similar lectins are consistent with a role in innate immunity in these invertebrates. [ABSTRACT FROM AUTHOR]

Background: Brucellosis, a zoonosis caused by the genus Brucella, has been eradicated in Northern Europe, Australia, the USA and Canada, but remains endemic in most areas of the world. The strain and biovar typing of Brucella field samples isolated in outbreaks is useful for tracing back source of infection and may be crucial for discriminating naturally occurring outbreaks versus bioterrorist events, being Brucella a potential biological warfare agent. In the last years MLVA-16 has been described for Brucella spp. genotyping. The MLVA band profiles may be resolved by different techniques i.e. the manual agarose gels, the capillary electrophoresis sequencing systems or the microfluidic Lab-on-Chip electrophoresis. In this paper we described a high throughput system of MLVA-16 typing for Brucella spp. by using of the microfluidics technology. Results: The Caliper LabChip 90 equipment was evaluated for MLVA-16 typing of sixty-three Brucella samples. Furthermore, in order to validate the system, DNA samples previously resolved by sequencing system and Agilent technology, were de novo genotyped. The comparison of the MLVA typing data obtained by the Caliper equipment and those previously obtained by the other analysis methods showed a good correlation. However the outputs were not accurate as the Caliper DNA fragment sizes showed discrepancies compared with real data and a conversion table from observed to expected data was created. Conclusion: In this paper we described the MLVA-16 using a rapid, sophisticated microfluidics technology for detection of amplification product sizes. The comparison of the MLVA typing data produced by Caliper LabChip 90 system with the data obtained by different techniques showed a general concordance of the results. Furthermore this platform represents a significant improvement in terms of handling, data acquiring, computational efficiency and rapidity, allowing to perform the strain genotyping in a time equal to one sixth respect to other microfluidics systems as e.g. the Agilent 2100 bioanalyzer. Finally, this platform can be considered a valid alternative to standard genotyping techniques, particularly useful dealing with a large number of samples in short time. These data confirmed that this technology represents a significative advancement in high-throughput accurate Brucella genotyping. [ABSTRACT FROM AUTHOR]

Between 2003 and 2008, 76 clinical isolates of the Panton–Valentine leukocidin-positive Staphylococcus aureus strain ‘West Australian methicillin-resistant Staphylococcus aureus (MRSA)-12’ (WA MRSA-12) were recovered from 72 patients living in the Perth area in Western Australia. These isolates were found to belong to multilocus sequence type 8, and had a USA300-like pulsed-field gel electrophoresis pulsotype. All isolates were genotyped using diagnostic DNA arrays covering species markers, resistance factors, virulence-associated, as well as MSCRAMM (microbial surface components recognizing adhesive matrix molecules) genes to prove the identity between WA MRSA-12 and the pandemic strain USA300, as well as to detect possible genetic variability. In general, WA MRSA-12 isolates were similar to USA300, and the most common variant was identical to USA300- . From this clone, most of the other variants may have evolved by a limited number of gene losses or acquisitions. Variations in carriage of virulence and resistance-associated genes allow distinction of variants or sub-clones. Altogether, 16 variants could be distinguished. They differed in the carriage of resistance genes ( blaZ/I/R, ermC, msrA + mpbBM, aadD + mupR, aphA3 + sat, tetK, qacC, merA/B/R/T) of β-haemolysin-converting phages and of enterotoxins ( sek + seq, which were deleted in four isolates). Notably, the arginine catabolic mobile element (ACME) was absent in 12 isolates (15.8%). The mercury resistance ( mer) operon, which is usually associated with SCC mec type III elements, was found in several ACME-negative isolates. The present study emphasises the importance of genotyping in detecting the introduction and evolution of significant MRSA strains within a community. [ABSTRACT FROM AUTHOR]

Allozyme electrophoresis was used to investigate the taxonomic status of northern calamary Sepioteuthis lessoniana (Lesson 1830) from two sites in Shark Bay, Western Australia. Of the 40 squid examined at 38 presumptive loci, four individuals from the oceanic site were clearly differentiated from the rest by fixed allelic differences at four loci (Acp, Got2, Idh2, and PepD) and near-fixed differences at another three (Est, Ocdh, and 6Pgd). The genetic distances between these two groups of individuals (13% Fixed Differences and Nei, D (1978)=0.178) were roughly twofold greater than those between the two cryptic taxa in the southern calamary S. australis, but are considerably smaller than those between the northern and southern calamary. The most likely explanation for these data is that S. lessoniana comprises two “cryptic” biological species in this region. Further studies are needed to delineate the total number of species found throughout Australasia for this important loliginid squid. [Copyright &y& Elsevier]

The group A Streptococcus (GAS) is an important pathogen that is responsible for a wide range of human diseases. Fibronectin binding proteins (FBPs) play an important role in promoting GAS adherence and invasion of host cells. The prtF2 gene encodes an FBP and is present in approximately 60% of GAS strains. In the present study we examined 51 prtF2-positive GAS strains isolated from the Northern Territory of Australia, and here we describe two genotypes of prtF2 which are mutually exclusive. The two genotypes have been identified previously as pfbp and fbaB. We show that these genotypes map to the same chromosomal location within the highly recombinatorial fibronectin-collagen-T antigen (FCT) locus, indicating that they arose from a common ancestor, and in this study these genotypes were designated the pfbp type and the fbaB type. Phylogenetic analysis of seven pfbp types, 14 fbaB types, and 11 prtF2-negative GAS strains by pulsed-field gel electrophoresis (PFGE) produced 32 distinct PFGE patterns. Interpretation of evolution based on the PFGE dendrogram by parsimony suggested that the pfbp type had a recent origin compared to the fbaB type. A comparison of multiple DNA sequences of the pfbp and fbaB types revealed a mosaic pattern for the amino-terminal region of the pfbp types. The fbaB type is generally conserved at the amino terminus but varies in the number of fibronectin binding repeats in the carboxy terminus. Our data also suggest that there is a possible association of the pfbp genotype with sof (84.2%), while the fbaB genotype was found in a majority of the GAS strains negative for sof (90.6%), indicating that these two prtF2 subtypes may be under different selective pressures. [ABSTRACT FROM AUTHOR]

Examines the genetic structure of enteric bacteria from Australian mammals. Characterization of Enterobacteriaceae using multi-locus enzyme electrophoresis; Variation of the genome diversity estimates among species; Use of molecular analysis variance; Relationship between effective population size and the genetic diversity of species.

Assesses the genetic relationships among isolates of Mycobacterium intracellulare and related species by the use of multilocus enzyme electrophoresis in Australia. Identification of Mycobacterium isolates; Presentation of the electrophoretic types, serovar and source of isolates; Genetic variation among strains of Mycobacteria.

We assessed changes in the microbial communities in ballast water during a trans-Pacific voyage from Japan to Australia that included a mid-ocean ballast-water exchange. Uncultured (i.e., total) and culturable bacteria were counted and were characterized by using denaturing gradient gel electrophoresis (DGGE). There was a clear decrease over time in numbers of uncultured microorganisms, except for heterotrophic nanoflagellates, whereas the abundance of culturable bacteria initially decreased after the ballast-water exchange but then increased. The increase, however, was only up to 5.34% of the total number of uncultured bacteria. Cluster analysis showed that the DGGE profiles of uncultured bacteria clearly changed after the exchange. In contrast, there was no clear change in the DGGE profiles of culturable bacteria after the exchange. Multidimensional scaling analysis showed changes in microbial communities over the course of the voyage. Although indicator microbes as defined by the International Convention for the Control and Management of Ships' Ballast Water and Sediments were occasionally detected, no coliform bacteria were detected after the exchange.

Coral bleaching has been identified as one of the major contributors to coral reef decline, and the occurrence of different symbionts determined by broad genetic groupings (clades A-H) is commonly used to explain thermal responses of reef-building corals. By using Stylophora pistillata as a model, we monitored individual tagged colonies in situ over a two-year period and show that fine level genetic variability within clade C is correlated to differences in bleaching susceptibility. Based on denaturing gradient gel electrophoresis of the internal transcribed spacer region 2, visual bleaching assessments, symbiont densities, host protein, and pulse amplitude modulated fluorometry, we show that subcladal types C78 and C8/a are more thermally tolerant than C79 and C35/a, which suffered significant bleaching and postbleaching mortality. Although additional symbiont types were detected during bleaching in colonies harboring types C79 and C35/a, all colonies reverted back to their original symbionts postbleaching. Most importantly, the data propose that the differential mortality of hosts harboring thermally sensitive versus resistant symbionts rather than symbiont shuffling/switching within a single host is responsible for the observed symbiont composition changes of coral communities after bleaching. This study therefore highlights that the use of broad cladal designations may not be suitable to describe differences in bleaching susceptibility, and that differential mortality results in a loss of both symbiont and host genetic diversity and therefore represents an important mechanism in explaining how coral reef communities may respond to changing conditions.

The distribution, host associations, and phylogenetic relationships of the unicellular cyanobacterial symbionts of selected marine sponges were investigated with direct 16s rDNA sequencing. The results indicate that the symbionts of the marine sponges Aplysina aerophoba, Ircinia variabilis, and Petrosia ficiformis from the Mediterranean, four Chondrilla species from Australia and the Mediterranean, and Haliclona sp. from Australia support a diversity of symbionts comprising at least four closely related species of Synechococcus. These include the symbionts presently described as Aphanocapsa feldmannii from P. ficiformis and Chondrilla nucula. A fifth symbiont from Cymbastela marshae in Australia is an undescribed symbiont of sponges, related to Oscillatoria rosea. One symbiont, Candidatus Synechococcus spongiarum, was found in diverse sponge genera in the Mediterranean Sea and the Indian, Pacific, and Southern oceans, whereas others were apparently more restricted in host association and distribution. These results are discussed in terms of the biodiversity and biogeographic distributions of cyanobacterial symbionts.

The spirochetes inhabiting the large intestines of humans and animals consist of a diverse group of related organisms. Intestinal spirochetosis caused by Serpulina pilosicoli is a newly recognized enteric disease of human beings and animals with potential public health significance. The purpose of this study was to determine the species identity of canine intestinal spirochetes by comparing 30 isolates obtained from dogs in Australia (n = 25) and the United States (n = 5) with reference strains representing Serpulina species and Brachyspira aalborgi, by phenotypic and genetically based typing methods. All of the canine isolates were indole negative and produced a weak beta-hemolysis when cultured anaerobically on agar medium containing blood. Four isolates were identified as S. pilosicoli by 16S rRNA-specific PCR assays, rRNA gene restriction fragment length polymorphism or ribotyping, and multilocus enzyme electrophoresis. The remaining 26 isolates formed a cluster related to porcine Serpulina innocens as determined by multilocus enzyme electrophoresis but had a unique ribotype pattern. The data suggested the existence of a novel Serpulina species, provisionally designated "Serpulina canis," colonizing the intestines of dogs.

Twenty-three alcohol dehydrogenase (ADH) putative null alleles extracted from four Tasmanian (Australia) populations of Drosophila melanogaster produce no ADH activity and are unable to form active heterodimers with either AdhF or AdhS. Twelve of these nulls were tested by enzyme-linked immunosorbent assay (ELISA) and did not produce any ADH cross-reacting material (CRM). The null homozygotes had similar, but slightly lower, mortalities on ethanol-supplemented media compared to an artificially induced null allele. Heterozygotes between the null alleles and standard AdhF and AdhS alleles had intermediate ADH activity and CRM levels.