P1 of strawberry vein banding virus, a multilocalized protein, functions as a movement protein and interacts with the coat protein

Although the complete nucleotide sequence of strawberry vein banding virus(SVBV) has been determined and bioinformatic analysis has revealed that the SVBV genome could encode seven proteins, the precise function of each protein is unclear. This study provided evidence that the P1 protein of SVBV(SVBV-P1) possesses the following features. Bioinformatic and subcellular localization analyses showed that SVBV-P1 is localized in the cytoplasm and cell walls of epidermal cells in Nicotiana benthamiana, and it forms inclusion bodies associated with microtubules and the endoplasmic reticulum. Dilution experiments demonstrated that SVBV-P1 could move from the original agro-infiltrated cells to adjacent cells in N. benthamiana leaves. Further trans-complementation experiments demonstrated that SVBV-P1 could facilitate the intercellular movement of a movement-deficient potato virus X mutant in N. benthamiana leaves. Finally, yeast twohybrid and bimolecular fluorescence complementation assays revealed that SVBV-P1 could interact with the SVBV coat protein, which is a major component of Caulimovirus virions. Results of the electrophoretic mobility shift assay indicated that SVBV-P1 lacks DNA-binding capability. In summary, the results suggest that SVBV-P1 is probably a movement protein of SVBV, providing new insights into the function of movement proteins of the Caulimovirus genus.

Strawberry vein banding virus P6 protein intracellular transport and an important domain identification

Strawberry vein banding virus （SVBV）-infected strawberry cells contain cytoplasmic inclusions with isometric particles. To identify the components of the inclusions, green fluorescent protein （GFP） was fused to the carboxy-terminus （C-terminus） of SVBV open reading frames, these constructs were separately transformed into Agrobacterium tumefaciens and infiltrated into Nicotiana benthamiana leaves. Results showed that the SVBV P6 protein assembled into prominent and amorphous inclusion bodies （IBs）. To investigate P6 subcellular localization, P6-GFP was ectopically expressed in N. benthamiana leaves by agroinfiltration and then stained with 4＂,6-diamidino-2-phenylindole （DAPI）. We found the P6 protein accumulated in the nuclei and also formed cytoplasmic IBs with different sizes. To further determine the location of P6 IBs in the cytoplasm, and explore whether the P6 IBs move freely or depend on cytoskeleton and endoplasmic reticulum （ER）, the microfilament marker protein （GFP-ABD2-GFP）, microtubules marker protein （mCherry-MAP65-1） and ER marker protein （mCherry-HDEL） were separately coexpressed with P6-GFP and into N. benthamiana leaves by agroinfiltration, exhibiting that P6 IBs aligned with cytoskeleton and endoplasmic reticulum. Meanwhile, coinfiltration of P1 and P6 indicated the P6 colocalized with the P1 protein at periphery of cells. The P6 protein contains one C-terminal nuclear localization signal （NLS） region, a P6 protein mutant with a deleted NLS did not localize in the nucleus, did not form IBs, and was unable to facilitate exogenous GFP expression. These results demonstrate that the deleted NLS region is an important P6 domain required for biological functions. In summary, the mobile P6 IBs are associated with ER, microfilaments and microtubules and move along microfilaments to the SVBV P1 protein in the PD.

一种手持式深紫外线发光二极管消毒器在食(饮)具消毒中的应用效果观察

目的观察一种手持式深紫外线发光二极管(UVC-LED)消毒器在食(饮)具中的消毒效果。方法采用载体定量杀菌试验和现场消毒试验方法,对该手持式UVC-LED消毒器的杀菌效果进行观察。结果该手持式UVC-LED消毒器辐射紫外线波长278 nm,输出功率200~450 mW/cm^(2)。该消毒器垂直作用距离25 cm,照射作用5 s,对载体上金黄色葡萄球菌、大肠埃希菌、铜绿假单胞杆菌和白色念珠菌杀灭对数值均>3.00。模拟现场消毒试验中,该UVC-LED消毒器对食(饮)具上大肠埃希菌垂直作用距离25 cm,作用5 s,杀灭对数值均>3.00;物体表面消毒现场试验中,其对办公桌表面100 cm^(2)垂直作用距离25 cm,照射作用30 s,对自然菌平均杀灭对数值>1.00。结论该手持式UVC-LED消毒器具有良好的消毒效果。

三种中药抑菌剂体外抑菌效果及其对皮肤黏膜刺激性观察

目的观察3种中药抑菌剂体外抑菌效果及其对皮肤黏膜刺激性,为实际应用提供科学依据。方法采用纸片法、稀释法和动物试验法,对3种中药抑菌剂体外抑菌效果及其皮肤黏膜刺激性进行观察。结果经对蛇床子、红花和黄柏3种中药抑菌剂观察结果显示,以红花抑菌剂抑菌作用最强,其对金黄色葡萄球菌、大肠杆菌和白色念珠菌的最低抑菌浓度分别为0. 78%、3. 12%和12. 50%;对上述3种细菌的抑菌环均在13 mm以上。3种中药抑菌剂对试验动物完整皮肤和眼黏膜刺激指数均为0。结论 3种中药抑菌剂对皮肤和眼黏膜均无刺激性,其中红花抑菌剂对3种试验菌均有较强的抑菌效果。

一种双癸基二甲基氯化铵皮肤消毒剂的消毒效果和安全性评价

目的观察一种双癸基二甲基氯化铵皮肤消毒剂的杀菌性能,并对其安全性进行评价。方法采用悬液定量杀菌试验及皮肤消毒现场试验观察该皮肤消毒剂的杀菌性能,采用动物毒性试验评价该皮肤消毒剂的安全性。结果含5 g/L SDS、10 g/L吐温80、10 g/L卵磷脂的0.03 mol/L PBS溶液能够有效中和该皮肤消毒剂对试验菌的残留作用。该皮肤消毒剂分别对悬液内大肠埃希菌、金黄色葡萄球菌和白色念珠菌作用1.5、3和4.5 min,均可以达到消毒合格;对30人次皮肤表面自然菌的平均杀灭对数值为1.68,符合要求;对豚鼠皮肤无刺激性,对小鼠骨髓嗜多染红细胞微核率无明显改变作用。结论该皮肤消毒剂具有良好的杀菌效果,安全性好,可以用作皮肤消毒。