成人做爰A片免费看网站网豆传媒,成人做爰黄级A片免费看土方,单身妈妈韩剧免费大全,女性hpv最初的征兆,被同桌摸到流水的黄文

RN4220

價格:3000元

聯系方式:I47-825O-882O

買家導航

金黃色葡萄球菌菌株基本信息

出品公司: --
感受態細胞名稱: RN4220
菌株類型: 金黃色葡萄球菌 Staphylococcus aureus
菌株來源: 金黃色葡萄球菌RN4220菌株,是利用紫外線UV和化學方法,誘導NCTC8325菌株產生的突變株。
產品目錄號: BF4220
培養基: MH 培養基,TSB培養基,Brain heart infusion Broth培養基
生長條件: 37 ℃,  有氧
基因型:  
抗性: 無抗
質粒轉化條件: 電轉
應用: 金黃色葡萄球菌基因操作
誘導方法: --
菌株特點:
RN4220一直以來被廣泛的應用于金葡菌基因研究。該菌株來源于NCTC8325-4,是一株限制性內切酶缺陷菌株,能夠接受來源于外部的其他物種的DNA質粒。RN4220體內沒有其他質粒,對大部分抗生素都敏感。

金葡菌RN4220是用來轉化大腸桿菌質粒DNA的金黃色葡萄球菌菌株。該菌株在基因sau1 hsdR上有突變,該突變的產生可以導致RN4220成為限制修飾系統基因缺陷型,可以用來作為大腸桿菌質粒DNA和金黃色葡萄球菌質粒轉化的中間宿主菌。該菌株基因型是mec陰性,rsbU陰性,agr陰性。MLST測序分型為8,e基因組SPA分型為59,e基因組SPA重復序列為YHGGFMBQBLO。 Ridom SPA分型為t211。RN4220的基因組序列已經測序成功,Genbank編號為AFGU00000000.1。
 
RN4220屬于甲氧西林敏感型金黃色葡萄球菌(MSSA)。

Electroporation of Staphylococcus aureus
(Hooper lab protocol)

1. Grow cells overnight in Brain Heart Infusion Broth (BHI).  3-5ml culture is sufficient.

2. Add 1ml of overnight culture to 100ml fresh BHI.  (OD550 should be ~ 0.010 at this point).  Grow at 37℃ (shaker table) until OD550 is 0.2-0.25.  Usually takes 2-2½ hours for BHI.  (Note:  Check OD initially after 2 hours.  For rapid growers like RN4220, it may already be at or near 0.2.  For other strains, it’s often in the 0.12-0.15 range.  Recheck every 15 minutes until culture reaches the target OD.  Electroporation efficiency drops off quite markedly once OD550 > 0.3).

3. Wash 4x with ice cold 0.5M sucrose (17% v/v).  Keep cold at this point.  Go from 100ml to 25ml to 10ml to 1ml.  Can use the table-top 4℃ Sorvall RT6000B centrifuge set at 9 for 3000 rpm.  Resuspend final pellet in ~500ul of 0.5M sucrose.

4. Add 160ul of cells to DNA.  Incubate on ice for 15 minutes.  Don’t use more than 20l of DNA in sterile water.  (With an new plasmid prep, reasonable to try 5ul, 10ul, and 20ul of a Qiagen MidiPrep of ~100-300ng/ul vector DNA.)  Concentrate DNA if need be.  (Otherwise, you’re at risk for arcing).

5. Electroporate.  Settings = 2.5kV, 200 Ohms, and 25uF.

6. Add 1ml BHI to cuvette, mix gently and transfer to sterile eppendorf tube, incubate at 30C 2 hours (30C because plasmids can be unstable at 37C in RN4220 independent of temp-sensitive origin of replication), and plate (50-200 ul of 1ml suspension) on appropriate antibiotic-selective BHI plates.

Notes
BHI is better than trypticase soy broth (TSB).

Use BioRad Gene Pulsar with 2mm cuvettes.

For chloramphenical, use 10ug/ml in plate.

For erythromycin, use 3-10ug/ml in plate.

For tetracycline, use 5ug/ml in plate.

The time constant for electroporation should be about 4.2-4.6 msec.

The cells can be frozen at –70C and used later but this will decrease the efficiency of transfer.  (I suspect that there’s a lot of cell death without glycerol in the media).

For 500ml 0.5M sucrose (MW 342.3 g/mole), add 85.6G sucrose in 500ml deionized water and filter sterilize (don’t autoclave).  Store at 4℃.

金黃色葡萄球菌菌株說明書pdf版和相關資料下載

金黃色葡萄球菌菌株應用舉例

分享到:
Copyright © 20012-2013 BIOFENG. 生物風 版權所有 Powered by Biofeng