Microbial and nematode communities associated with potatoes genetically modified to express the antimicrobial peptide magainin and unmodified potato cultivars     

Maureen O’Callaghan  Emily M. Gerard  Nigel L. Bell  Nick W. Waipara  Lee T. Aalders  David B. Baird  Anthony J. Conner 《Soil biology & biochemistry》2008,40(6):1446-1459

The antimicrobial peptide magainin II has activity against a range of micro-organisms. Tubers harvested from potatoes genetically modified (GM) to express a synthetic magainin gene show improved resistance to the bacterial pathogen Erwinia carotovora. The microbial and nematode communities associated with three magainin-expressing potato lines, their near-isogenic, unmodified parental cultivar (Iwa) and an unrelated cultivar (Karaka) were investigated on field-grown plants. Heterotrophic plate counts were used to enumerate aerobic culturable bacterial and fungal populations, while cultivation-independent analysis of bacterial communities was based on denaturing gradient gel electrophoresis (DGGE) of 16S rRNA gene fragments amplified from community DNA from phyllosphere, rhizosphere and geocaulosphere (tuber surface) samples. Small but statistically significant differences in the population sizes of culturable bacteria, fungi and yeast were detected among some GM magainin-expressing lines and the unmodified control. However, these differences were typically smaller than the differences between the unmodified parental line control (Iwa) and the unrelated cultivar control (Karaka). Similarly, the difference in the proportion of the nematode population belonging to the fungal feeding trophic group between Iwa and Karaka was greater than that amongst Iwa and its near-isogenic GM lines, and was significantly so for the genus Aphelenchus. The nematode channel ratio (NCR) indicated a more fungal-dominated decomposition channel in soil beneath Karaka compared to Iwa at harvest. In general, eubacterial phylloplane communities were similar for all lines, while the rhizosphere communities associated with two of the three GM lines differed from communities associated with their unmodified parental line control. When roots were senescent, there was no significant difference among potato lines in rhizosphere eubacterial communities or individual trophic groups of the nematode community. Greater diversity was found in geocaulosphere; α-proteobacteria and actinomycete communities of two of the three GM lines differed significantly from their unmodified parental line control and the unrelated cultivar control, while the communities associated with the third GM line were more similar to those of the two control lines. This highlights the importance of testing several GM lines when assessing non-target effects. Results suggest that there is little likelihood of any major sustained non-target effect of genetic modification using a magainin II transgene on plant-associated and soil microflora and function.  相似文献   

Atomic description of an enzyme reaction dominated by proton tunneling     

Masgrau L  Roujeinikova A  Johannissen LO  Hothi P  Basran J  Ranaghan KE  Mulholland AJ  Sutcliffe MJ  Scrutton NS  Leys D 《Science (New York, N.Y.)》2006,312(5771):237-241

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Fungicidal sesquiterpene dialdehyde cinnamates from Pseudowintera axillaris   总被引：1，自引：0，他引：1  

Brennan NJ  Larsen L  Lorimer SD  Perry NB  Chapin EL  Werk TL  Henry MJ  Hahn DR 《Journal of agricultural and food chemistry》2006,54(2):468-473

Bioactivity-directed separation of a foliage extract from the New Zealand shrub Pseudowintera axillaris led to a compound with fungicidal activity against the plant pathogen Phytophthora infestans. This was identified as a new sesquiterpene dialdehyde cinnamate named paxidal. Two 6-hydroxy derivatives were present at lower levels in the extract. A further nine derivatives were synthesized from these natural products for a structure-activity study against a range of important food crop pathogens. The cinnamate group was important for fungicidal effects, and protection of the dialdehyde as a dimethyl acetal gave more potent, broader spectrum activity.  相似文献   

Obstruction of equine small intestine associated with focal idiopathic eosinophilic enteritis: An emerging disease?     

Archer DC  Barrie Edwards G  Kelly DF  French NP  Proudman CJ 《Veterinary journal (London, England : 1997)》2006,171(3):504-512

Idiopathic focal eosinophilic enteritis (IFEE) is a rare disease in the horse and few cases have been reported in the literature. The objective of this paper was to describe the clinical, surgical, histological features and post-operative progress of 12 horses with IFEE, a disease that had not been identified in the authors' hospital population prior to 2000. Diagnosis of IFEE was made at laparotomy and confirmed by histological examination of resected abnormal small intestine. In all 12 horses colic was associated with jejunal obstruction involving visibly striking and palpably thickened serosal plaques or circumferential constrictions. Surgical resection of affected intestine was performed in 10 horses, of which seven completely recovered. In one horse, on which surgical resection was not performed, ingesta re-obstructed post-operatively at one of the lesions. Histological examination of resected intestines revealed, in all cases, severe transmural enteritis in which eosinophilic leucocytes were the predominant inflammatory cells. No helminths were identified and the cause of this lesion is not known. IFEE is an uncommon but significant cause of small intestinal obstruction for which surgical resection can be curative. The gross lesions may be under-recognised and histology is essential for diagnosis.  相似文献   

Correction to: A prioritised inventory of crop wild relatives and wild harvested plants of Tunisia     

El Mokni  Ridha  Barone  Giulio  Maxted  Nigel  Kell  Shelagh  Domina  Gianniantonio 《Genetic Resources and Crop Evolution》2022,69(7):2605-2620

Genetic Resources and Crop Evolution -  相似文献