JM109感受态细胞

Bacterial Strain JM109 is a useful host for transformation of pGEM® Vectors and for production of single-stranded DNA from M13 or phagemid vectors. The strain grows well and is transformed efficiently by a variety of methods. Because JM109 is recA– and lacks the E. coli K restriction system, undesirable restriction of cloned DNA and recombination with host chromosomal DNA are prevented. The endonuclease A– mutation leads to an improved yield and quality of isolated plasmid DNA.

JM109 is deficient in β-galactosidase activity due to deletions in both genomic and episomal copies of the lacZ gene. The deletion in the episomal (F´ factor) copy of the lacZ gene (lacZΔM15) can be complemented by addition of a functional α-peptide encoded by a pGEM®-Z or pGEM®-Zf Vector. If complementation does not occur, bacterial colonies are white. To maintain the F´, JM109 should be grown on minimal (M-9) media supplemented with 1mM thiamine.

Genotype: endA1, recA1, gyrA96, thi, hsdR17 (rk–, mk+), relA1, supE44, Δ( lac-proAB), [F´ traD36, proAB, laqIqZΔM15].

Features - Benefits

• Reliable: Grows well and is transformed efficiently.
• Versatile: Useful for cloning, single-stranded DNA production, and blue/white screening.
• High Yields of Plasmid DNA: The endonuclease A– mutation improves yield and quality of isolated plasmid DNA.

Applications

• Blue/white color screening of pGEM®-Z and pGEM®-Zf(+/–) Vectors in the presence of X-Gal and IPTG.
• 菌种培养及打管说明：
  1、安瓿瓶开封：用浸过75％酒精的脱脂棉擦净安瓿管，用火焰加热其顶端，滴少量无菌水至加热顶端使之破裂，用锉刀或者镊子敲下已破裂的安瓿管顶端。
  2、菌株恢复培养：用无菌吸管吸取0.3--0.5ml适宜的液体培养基，滴入安瓿管内，轻轻振荡，使冻干菌体溶解呈悬浮状。吸取全部菌体悬浮液，移植于1-2支建议的培养基试管中，并在建议的条件下培养。
  3、注意事项：菌种活化前，请将安瓿管保存在6-10℃的环境下，某些菌种经过冷冻干燥保存后，延迟期较长，需要连续两次继代培养才能正常生长
  4、复苏后的菌种在传1-2代后使用。
  5、暂不启开的安瓿及复苏后需保藏的斜面应于4℃中保藏。
  特别注意事项：
  l、微生物菌种应保藏于低温、清洁和干燥的地方,室温放置时问过长会导致菌种衰退;
  2、菌种操作应在无菌条件下进行,防止杂菌污染:
  3、斜面菌种保藏时间通常为1-2个月,应根据菌种状况及时转接;冻干菌种保藏时间通常为5~10年;
  4、菌种使用过程中如出现杂菌污染或菌种生产性能下降，应及时与我司销售联系或更换新的菌种。