A bioaugmentation failure caused by phage infection and weak biofilm formation ability

Two biological aerated filters （BAF） were setup for ammonia removal treatment of the circulation water in a marine aquaculture. One of the BAFs was bioaugmented with a heterotrophic nitrifying bacterium, Lutimonas sp. H10, where the ammonia removal was not improved and the massive inoculation was even followed by a nitrification breakdown from day 9 to 18. The nitrification was remained stable in control BAF operated under the same conditions. Fluorescent in situ hybridization （FISH） with rRNA-targeted probes and cultivable method revealed that Lutimonas sp. H10 almost disappeared from the bioaugomented BAF within 3 d, and this was mainly due to the infection of a specific phage as revealed by flask experiment, plaque assay and transmission electron observation. Analyses of 16S rRNA gene libraries showed that bacterial groups from two reactors evolved differently and an overgrowth of protozoa was observed in the bioaugmented BAF. Therefore, phage infection and poor biofilm forming ability of the inoculated strain are the main reasons for bioaugmentation failure. In addition, grazing by protozoa of the bacteria might be the reason for the nitrification breakdown in bioaugmented BAF during day 9-18.

A novel t(3;12)(q21;p13) translocation in a patient with accelerated chronic myeloid leukemia after imatinib and nilotinib therapy

The acquisition of secondary chromosomal aberrations in chronic myeloid leukemia (CML) patients with Philadelphia chromosome-positive (Ph+) karyotype signifies clonal evolution associated with the progression of the disease to its accelerated or blastic phase. Therefore, these aberrations have clinical and biological significance. T(3;12)(q26;p13), which is a recurrent chromosomal aberration observed in myeloid malignancies, is typically associated with dysplasia of megakaryocytes, multilineage involvement, short duration of any blastic phase, and extremely poor prognosis. We have identified a recurrent reciprocal translocation between chromosomes 3 and 12 with different breakpoint at bands 3q21 in the malignant cells from a 28-year-old man. The patient was initially diagnosed as having Ph+ CML in the chronic phase. The t(3;12)(q21;p13) translocation occurred 4 years after the patient was first diagnosed with CML while undergoing tyrosine kinase inhibitor therapy. We confirmed the t(3;12)(q21;p13) translocation via fluorescence in situ hybridization assay by using whole-chromosome paint probes for chromosomes 3 and 12. Our findings demonstrate that, similar to other recurrent translocations involving 3q26 such as t(3;3) and t(3;21), the t(3;12)(q21;p13) translocation is implicated not only in myelodysplastic syndrome and acute myeloid leukemia but also in the progression of CML. These findings extend the disease spectrum of this cytogenetic aberration.

Development and characterization of synthetic amphiploids of Oryza sativa and Oryza latifolia

Oryza sativa and Oryza latifolia belong to the AA and CCDD genomes of Oryza, respectively. In this study, amphiploids were obtained from the tube seedlings of O. sativa × O. latifolia F1 hybrids by treatment with colchicine, an agent for chromosome doubling. Subse- quently, amphiploids were investigated using the methods of morphology, genomic in situ hybridization, and molec- ular markers. Amphiploids were characterized by a shorter plant height, larger diameter of stem, longer and wider leaves, darker leaf color, decreased spikelets per panicle and panicle length, and larger spikelets and anthers than the original F1 hybrid. Based on the mitotic metaphase chro- mosome number of the investigated root tips, the somatic chromosome number of the amphiploid is 2n = 72. Additionally, the amphiploid is an allohexaploid, and its genomic constitution is AACCDD by genomic in situ hybridization analysis. Finally, the amphiploids were identified to be true using 37 polymorphic markers at the DNA level.