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A bacterial strain, designated CY22, was isolated from the interior of balloon flower (Platycodon grandiflorum) root in the Republic of Korea. The isolate coproduced an iturin-like antifungal compound and a surfactin-like potent biosurfactant. Analysis of the 16S-rDNA of strain CY22 showed that the isolate was a member of Bacillus. High similarities were observed between strain CY22 and Bacillus sp. TKSP 24, and between strain CY22 and B. subtilis 168. Phylogenetic analysis based on 16S-rDNA sequences showed that strain CY22 was closely related to Bacillus sp. The main whole-cell fatty acids were anteiso-C15:0 (37%), C17:0 (5.1%), and iso-C15:0 (27.7%). DNA G + C content was 54 mol%. Based on phylogenetic inference, phenotypic and chemotaxonomic characteristics, this endophytic strain Bacillus sp. CY22 was assigned to the genus Bacillus.  相似文献   
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Conjugational transfer of pLS20 in Bacillus subtilis Marburg 168 is restricted by the BsuM restriction-modification system. Restriction efficiency was measured using pLS20 derivatives possessing various numbers of XhoI sites, which are known to be recognized by BsuM. An increase in XhoI sites clearly reduced the conjugational efficiency of pLS20 as compared with that of pUB110 plasmid lacking XhoI.  相似文献   
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Abstract The genes encoding the CryIVB and CryIVD crystal polypeptides of B. thuringiensis subsp. israelensis were cloned indepently on a stable shuttle vector, and transfered into B. sphaericus 2297. Recombinant cells expressed the B. thuringiensis toxins during sporulation and were shown to be toxic to Aedes aegypti fourth instar larvae, whereas the parental strain was not.  相似文献   
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Soldiers routinely conduct load carriage and physical training to meet occupational requirements. These tasks are physically arduous and are believed to be the primary cause of musculoskeletal injury. Physical training can help mitigate injury risk when specifically designed to address injury mechanisms and meet task demands. This study aimed to assess lower-limb biomechanics and neuromuscular adaptations during load carriage walking in response to a 10-week evidence-based physical training program. Thirteen male civilian participants donned 23 kg and completed 5 km of load carriage treadmill walking, at 5.5 km h−1 before and after a 10-week physical training program. Three-dimensional motion capture and force plate data were acquired in over-ground walking trials before and after treadmill walking. These data were inputs to a musculoskeletal model which estimated lower-limb joint kinematics and kinetics (i.e., moments and powers) using inverse kinematics and dynamics, respectively. A two-way analysis of variance revealed significant main effect of training for kinematic and kinetics parameters at the knee and ankle joints (p < 0.05). Post-Hoc comparisons demonstrated a significant decrease (4.2%) in total negative knee power between pre- and post-March 5 km measures after training (p < 0.05). Positive power contribution shifted distally after training, increasing at the post-march measure from 39.9% to 43.6% at the ankle joint (p < 0.05). These findings demonstrate that a periodised training program may reduce injury risk through favourable ankle and knee joint adaptations.  相似文献   
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The influence of nonionic surfactants on the activity of a novel thermostable lipase from Bacillus stearothermophilus MC7 was investigated with a view to its potential for synthesis of structured lipids. A large number of modifiers within a broad concentration range were applied. The activity of the enzyme was measured at a relatively high reaction temperature. Highest degree of activation was observed when PEG6000 was applied (up to 2.3-fold increase). Modification essentially changed the performance of the lyophilised preparations—they keep up to 80% of the activity of the native enzyme in the presence of a detergent against 30% in its absence. The effect of sorbitan esters (spans) and polyoxyethylene derivatives of sorbitan esters (tweens) on lipase MC7 was estimated, their HLB value varying within the interval 2.1–16.7. Tweens were strong inhibitors at higher concentrations. For all spans, excepting span 60, an increase of enzyme activity with concentration was observed. All studied additives slow down the process of thermal denaturation. Lipase preparations preserve more than 60% of their activity after 30-min incubation at 75 °C in the presence of tween 60 or PEG4000.  相似文献   
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