Both Bacillus sphaericus and Bacillus thuringiensis subsp. israelensis produce mosquitocidal toxins during sporulation and are extensively used in the field for control of mosquito populations. All the known toxins of the latter organism are known to be encoded on a large plasmid, pBtoxis. In an attempt to combine the best properties of the two bacteria, an erythromycin resistance-marked pBtoxis plasmid was transferred to B. sphaericus by a mating technique. The resulting transconjugant bacteria were significantly more toxic to Aedes aegypti mosquitoes and were able to overcome resistance to B. sphaericus in a resistant colony of Culex quinquefasciatus, apparently due to the production of Cry11A but not Cry4A or Cry4B. The stability of the plasmid in the B. sphaericus host was moderate during vegetative growth, but segregational instability was observed, which led to substantial rates of plasmid loss during sporulation.

Aims:  To develop a rapid real‐time polymerase chain reaction (PCR) method to detect Gluconobacter and Gluconacetobacter species in electrolyte replacement drinks. Methods and Results:  Samples of electrolyte replacement drinks were artificially contaminated with Gluconobacter species and then filtered to collect cells. DNA was extracted from the filters and analysed by real‐time PCR on the ABI Prism 7000 system, using commercial detection kits for lactic and acetic acid bacteria. In addition, specific primers and Taqman® probe were designed and used for the detection of seven Gluconobacter and Gluconacetobacter species. All the assays tested demonstrated a linear range of quantification over four orders of magnitude, suggesting detection levels down to 1 CFU ml−1 in the original drink. Conclusions:  A real‐time PCR method was developed to detect low concentrations of Gluconobacter and Gluconacetobacter sp. in an electrolyte replacement drink. Significance and Impact of the Study:  Real‐time PCR methods allow a rapid, high throughput and automated procedure for the detection of food spoilage organisms. The real‐time PCR assay described is as sensitive as the conventional method that involves pre‐enrichment, enumeration on a selective agar (typically malt extract agar) and identification with a differential medium (typically Wallerstein nutrient agar). The real‐time PCR assay also provides a more rapid rate of detection, with results in less than 24 h following enrichment for Gluconobacter and Gluconacetobacter species.

Differences in activation between spores from strains of Bacillus thuringiensis subsp. israelensis with and without the toxin-encoding plasmid pBtoxis are demonstrated. Following alkaline activation, the strain bearing pBtoxis shows a significantly greater germination rate. Expression of just three genes constituting a previously identified, putative ger operon from this plasmid is sufficient to produce the same phenotype and characterizes this operon as a genetic determinant of alkaline activation.Bacillus thuringiensis is a member of the Bacillus cereus sensu lato complex of bacilli and is distinguished by its ability to produce parasporal crystalline inclusions that may be toxic to invertebrates, usually insects (13). Spores and crystals are ingested by susceptible larvae, and the constituent Cry and/or Cyt crystal proteins are solubilized and proteolytically processed in the gut to release the active toxins (7). B. thuringiensis spores are able to germinate in the intoxicated larva and exploit the rich nutrient resources of the insect cadaver. Germination is triggered in response to germinants, usually nutrients that signal favorable conditions for growth (15). Like other B. cereus group bacteria, B. thuringiensis will germinate in response to nonspecific germinants, such as nutrient broth, and to specific germinants including L-alanine or ribonucleosides, such as inosine, and the process can be visualized by a loss of phase brightness (2).In the laboratory, spores can be "activated" (induced to relatively synchronous germination) by conditions such as brief sublethal heat treatment or preincubation in an alkaline environment. The latter treatment is used most often in laboratories studying B. thuringiensis since such a treatment is more physiologically relevant than heat activation because most insects have alkaline guts in which the pH stimulates germination (18). Despite this interesting and relevant phenomenon, the genetic basis for alkaline activation has not been elucidated, although an association between alkaline activation and crystal production in strains of Bacillus thuringiensis subsp. kurstaki and B. thuringiensis subsp. israelensis has been noted (2, 4).The genes encoding the crystal toxins are usually extrachromosomally borne on high-molecular-weight, stringent plasmids (14), and to date the sequence of only one such plasmid, pBtoxis from B. thuringiensis subsp. israelensis, has been reported (3). In addition to genes encoding four Cry proteins and three Cyt proteins, pBtoxis appears to encode a range of other proteins, including factors that may be involved in spore germination. The pBtoxis genes pBt084, pBt085, and pBt086 show similarities to previously reported ger genes (encoding proteins similar to the Bacillus subtilis germination protein GerAC and B. cereus proteins GerIB and GerIA, respectively). In addition, the plasmid bears two apparent pseudogenes, pBt060 and pBt063, that are similar to pBt086 and pBt085, respectively (3). Transcriptional analysis showed no mRNA production from the...

In Greece, the economic situation has been dire in recent years: Unemployment is near 30%, and public spending has been slashed because of austerity measures imposed by the European Union. A new study looking at the Greek capital’s wastewater shows how the public has responded to the societal stress: The use of many legal and illegal substances—particularly antipsychotics and antidepressants—has skyrocketed since the EU bailout plan took effect in 2010 (Environ. Sci. Technol. 2016, DOI: 10.1021/acs.est.6b02417). Nikolaos S. Thomaidis of the University of Athens and colleagues collected wastewater samples from Athens’s treatment plant for about a week each year from 2010 to 2014. Then they used liquid chromatography and mass spectrometry to screen for 148 legal and illegal drugs and their related metabolites. The team found huge increases in the levels of antipsychotics (35-fold), benzodiazepines (19-fold), and antidepressants (11-fold), correlating with the fall of Greece’s gross domestic product and the

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