Primer extension analysis of transcripts of the Bacilus subtilis autolysin (cwlB) operon indicated that SigD-dependent transcripts from the Pd promoter are missing in the degU32(Hy) and degS200(Hy) mutants. The degU32(Hy) mutation caused a 990% reduction in the expression of a sigD-lacZ translational fusion gene constructed in the B. subtilis chromosome. The phosphorylated form of the DegU protein seems to be a regulator for expression of the sigD gene.Bacillus subtilis produces two major autolysins (N-acetylmuramoyl-L-alanine amidase and endo-o-N-acetylglucosaminidase) during the vegetative growth phase (7,8,12,28). A gene encoding the former protein (CwlB) has been cloned by us and others (15,18), and it is the third gene in an operon consisting of three genes which encode a putative lipoprotein (LppX), a modifier protein (CwbA), and CwlB, in that order (14,15,18). Transcription of the cwlB operon mainly depends on expression of the SigD protein, which is responsible for cell motility and chemotaxis (16,20). Recently, we cloned a cwlG gene encoding an endo-p-N-acetylglucosaminidase and constructed a double mutant deficient in the two above-mentioned autolysins. The double mutant exhibited greatly impaired motility on a swarm plate, whereas single mutants were motile (27). One of the pleiotropic genes, sin(flaD), is involved in the control of many late-growth developmental processes (32). The sin(flaD) mutation results in an increase in alkaline protease, a filamentous cell morphology, poor development of competence, loss of motility, and a decreased level of autolysin (30, 32). We previously focused on the positive function of sin(flaD) in autolysin production (16,30). A mutation in the C-terminal region of Sin(SinR, FlaD) (3) significantly decreased the expression level of the sigD gene (16). Primer extension analysis indicated that transcription from the sigma D promoter (Pd) of the cwlB operon does not occur in the case of the sin(flaDl) mutant. Moreover, transcription from the sigma A promoter (Pa) also did not occur (16).The degS and degU genes form an operon encoding a two-component system (11,13,23,24,33). Two classes of mutation that have been found in both the degS and degU genes lead either to a deficiency of degradative enzyme production or a pleiotropic Hy phenotype, which includes hyperproduction of degradative enzymes, the ability to sporulate in the presence of glucose, poor development of competence, a filamentous cell morphology, and loss of flagella and motility (2,11,23,31,33 for degradative enzyme production and appears to act as a repressor of essential components of the competence development pathway encoded by the srfoperon (5,9,24). A nonphosphorylated form of DegU is also required for the development of competence, i.e., late competence genes such as comG (6,29). It has been suggested that the degU(Hy) allele may regulate some step(s) upstream from hag (structural gene for flagellin) (22) and degR (accessory regulatory peptide for DegS-DegU) (26,34,35). We report here that the degU(Hy)...

We investigated the reproductive and lifetime performances of Kagoshima Berkshire gilts and sows. We examined 20 605 parity records of 4419 pigs for 2008 to 2012 on a farrow-to-finish commercial farm. The mean parity (± SD) of all animals was 3.0 ± 2.1. For farrowing performance, the highest numbers of total pigs born and pigs born alive were found in sows with parities 5 and 6 and with parity 3-6, respectively (P < 0.05). Regarding weaning and mating performance, sows with parity 2 had the lowest preweaning mortality (P < 0.05). The longest weaning-to-first-mating interval was found in parity 1 pigs, and the interval decreased as parity increased (P < 0.05). Parities 0 and 1 pigs had the lowest farrowing rate and those with parity 4 had the highest farrowing rate (P < 0.05). The mean parity at culling, total number of pigs born alive in a lifetime, and nonproductive days in a lifetime were 5.5 ± 2.93, 49.2 ± 24.72 pigs, and 132.1 ± 83.34 days, respectively. These animals had a lower litter size and fertility that the F1 crossbred sows mainly used in Japan, but a similar tendency for performance by parity.

Tellurite is highly toxic to most bacteria owing to its strong oxidative ability. However, some bacteria demonstrate tellurite resistance. In particular, some Escherichia coli strains, including Shiga toxin-producing E. coli O157:H7, are known to be resistant to tellurite. This resistance is involved in ter operon, which is usually located on a prophage-like element of the chromosome. The characteristics of the ter operon have been investigated mainly by genome analysis of pathogenic E. coli; however, the distribution and structural characteristics of the ter operon in other E. coli are almost unknown. To clarify these points, we examined 106 E. coli strains carrying the ter operon from various animals. The draft genomes of 34 representative strains revealed that ter operons were clearly classified into four subtypes, ter-type 1–4, at the nucleotide sequence level. Complete genomic sequences revealed that operons belonging to three ter-types (1, 3, and 4) were located on the prophage-like elements on the chromosome, whereas the ter-type 2 operon was located on the IncHI2 plasmid. The positions of the tRNASer, tRNAMet, and tRNAPhe indicated the insertion sites of elements carrying the ter operons. Using the PCR method developed in this study, 106 strains were classified as type 1 (n = 66), 2 (n = 13), 3 (n = 8), and 4 (n = 17), and two strains carried both types 1 and 2. Furthermore, significant differences in the minimum inhibitory concentration (MIC) of tellurite were observed between strains carrying ter-type 4 and the others (p &lt; 0.05). The ter-type was also closely related to the isolation source, with types 2 and 4 associated with chickens and deer, respectively. This study provided new insights related not only to genetic characteristics of the ter operons, but also to phenotypic and ecological characteristics that may be related to the diversity of the operon.

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