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Tunable diode laser absorption spectroscopy (TDLAS) was evaluated on its potential to detect bacterial growth of contaminated media fill vials. The target was a replacement/ automation of the traditional visual media fill inspection. TDLAS was used to determine non-invasively O 2 and/or CO 2 changes in headspaces of such vials being induced by metabolically active microorganisms. Four different vial formats, 34 microorganisms (inoculation volume<10 cells) and two different media (TSB/FTM) were tested. Applying parallel CO 2 and O 2 headspace measurements all format-organism combinations were detected within <11 days reliably with reproducible results. False negatives were exclusively observed for samples that were intentionally breached with syringes of 0.3mm in diameter. Overall it was shown that TDLAS functionality for a replacement of the visual media fill inspection is given and that investing in further validation and implementation studies is valuable. Nevertheless, some small but vincible challenges remain to have this technology in practical use., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Alternative poultry production with special reference to free range broilers has increased significantly since the nineties in many regions of the world. Numerous factors influence the productive performance of this type of broilers: genotype (namely the use of naked neck animals), feeding and access to an outdoor area. The aim of this paper is to study the influence of each of these factors on the productive performance of free range broilers under commercial rearing conditions. A total of 3200, day old chicks of both sexes from naked neck and normally feathered genotypes were used in this trial. After a joint initiation phase, animals were divided into four different treatments with the combination of two concentrates (high vs low energy content) and management (access to outside park or not). Experiment lasted a total of 12 weeks. Live weight date was recorded weekly and a samples of animals from the trial were sacrificed at the age of 8, 10 and 12 weeks, when carcass characteristics were determined. Besides sex, the only factor that seems to affect growth characteristics was genotype as naked neck animals had poorer growth rates than normally feathered. No effect was detected on carcass yields and percentages of carcass components for any of the variables. From the data presented in this trial the practises associated with free range production are of relative inconsequence to the technical animal production parameters and can only be justified by a pressing need to differentiate these products from standard poultry products in what concerns both welfare issues and meat characteristics. The results also indicate that genetic material from alternative poultry production in Europe can be a useful option in poultry production development projects in the tropics.

FtsH is a membrane-bound and energy-dependent metalloprotease in bacteria which is involved in the posttranslational control of the activity of a variety of important transcription factors and in the degradation of uncomplexed integral membrane proteins. For Bacillus subtilis, little is known about the target proteins of FtsH protease. Its gene is not essential, but knockout strains display a pleiotropic phenotype including sensitivity toward salt and heat stress, defects in sporulation and competence, and largely filamentous growth. Comparison of the intracellular proteomes of wild-type and ftsH knockout strains revealed that at least nine proteins accumulated in the absence of ftsH, four of which could be identified. Two of these proteins turned out to be members of the sigma(W) regulon. Accumulation of one of these sigma(W)-controlled proteins, the penicillin-binding protein PBP4*, was analyzed in more detail. We could show that PBP4* is not a proteolytic substrate of FtsH and that its overproduction is due to the enhanced transcription of its gene (pbpE) in ftsH null mutants. The filamentous growth phenotype of DeltaftsH strains was abolished in a DeltaftsH DeltapbpE double knockout. In ftsH wild-type strains with the pbpE gene under regulatable control, pbpE overexpression caused filamentation of the cells. DNA macroarray analysis revealed that most genes of the sigma(W) regulon are transcribed at elevated levels in an ftsH mutant. The influence of FtsH on sigma(W)-controlled genes is discussed.

A Bacillus subtilis disruption mutant with a mutation in sigI (formerly ykoZ) shows a temperature-sensitive growth on agar plates. The transcription of the sigI gene is heat shock induced in rich medium but not in minimal medium. Proteome studies revealed a reduced amount of GsiB protein in the sigI mutant under heat shock conditions.

The IepA operon of Bacillus subtilis was found to be bicistronic and to consist of the two genes IepA and hemN, which encode a putative GTP-binding protein and an oxygen-independent coproporhyrinogen III oxidase, respectively. The IepA operon is located immediately upstream of the dnaK operon. Both operons are transcribed in the same direction and are not separated by an obvious transcription-terminator-like structure. The IepA operon is preceded by a potential vegetative promoter, and there is a putative strong intergenic terminator between IepA and hemN. Northern blot experiments revealed only a transcript corresponding to IepA, but expression of hemN was demonstrated in slot-blot and immunoblot experiments using antibodies raised against His-tagged HemN. The data suggest that most of the transcripts originating at the potential vegetative promoter are terminated at the intergenic terminator. Readthrough transcription into the downstream dnaK operon was not found.

A method for the rapid restriction mapping of large plasmids has been developed. A 400-bp fragment of phage lambda DNA containing the cos region has been inserted into Tn5. After in vivo transposition of this Tn5cos element into the plasmid of choice, the plasmid is isolated and linearized at its cos site with phage lambda terminase (Ter). Such Ter linearization was about 70% efficient. After partial digestion of the linear molecules with the appropriate restriction enzyme, the products are selectively labelled at the right or left cohesive phage lambda DNA termini by hybridization with digoxygenin (DIG)-11-dUTP-labelled (using terminal transferase) oligodeoxyribonucleotides complementary to the single-stranded cos ends. After pulsed field gel electrophoresis, the labelled fragments are visualized in the dried gel using a DIG-detection kit. The restriction map can be directly determined from the 'ladder' of partial digestion products.