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全部话题 - 话题: monomer
1 2 3 4 5 6 7 下页 末页 (共7页)
e********r
发帖数: 147
1
最近我们体外实验发现一个蛋白同时存在monomer和trimer形式,有意思的是,monomer
状态下,能够结合另一个蛋白,激活下游基因的表达。
现在想在体内in vivo检查一下不同刺激条件下,monomer和trimer之间比率的变化。以
前没做过类似的工作,请问应该肿么搞?刺激前后把蛋白交联起来,然后跑SDS-PAGE,
Western blotting这样的方法可行不?非常感谢。
m*****e
发帖数: 1506
2
You may want to modifiy your monomer, re-link the vinyl group and pendant
functional group of your monomer using a longer spacer,and also try to redue
the rigidity of your monomer structure.
z*****y
发帖数: 7
3
Does anyone know if there are commercially available acrylic or methacrylic
monomers containing ketone group? Methacrylamide and acrylamide monomers are
also interesting for me. Thanks in advance.
h****k
发帖数: 182
4
请问有什么好的方法或者实验可以检测membrane bound receptor 是monomer,dimer,
还是multimer?
h****k
发帖数: 182
5
谢谢ls。我会先选择native gel试试看。另外sec不可行因为蛋白量不够。还有cross
linking可能会把本来是monomer的link成dimer 或者multimer?? 感觉不对。
C*********h
发帖数: 83
6
两篇文章采用了不同的方法。供参考。
以前有人贴过。
###
NIH 刘正刚实验室 在2014年一月的NCB文章中,刘正刚也show MLKL可以形成三聚体同
时跑到细胞膜上,并激活下游的钙离子通道,来导致细胞坏死。
Nat Cell Biol. 2014 Jan;16(1):55-65. doi: 10.1038/ncb2883. Epub 2013 Dec 8.
Plasma membrane translocation of trimerized MLKL protein is required for TNF
-induced necroptosis.
厦门大学 韩家淮实验室几乎在同一时间,在Cell Research上发表了另外一篇paper。
Cell Research (2014) 24:105–121. doi:10.1038/cr.2013.171; published online
24 December 2013
Translocation of mixed lineage kinase domain-like protein to plasma membrane... 阅读全帖
d**a
发帖数: 3715
7
If my monomer (aromatic compound) has a very poor solubility in THF or
toluene, then how it can be polymerized?
m*****e
发帖数: 1506
8
try polar solvents like DMF or DMSO
try polymerization at high temperature
it also depends on what kind of monomer and what kind of polymerization.
d**a
发帖数: 3715
9
Thank you for your reply. The monomer is a multi-ring aromatic compound,
very difficult to dissolve in DMF at 80 oC.
I am currently trying a free radically polymerization process.
c*s
发帖数: 2145
10
sounds like steric effect plays a role and you might try copolymerize with
other monomer
d**a
发帖数: 3715
11
en,make sense. Previously this monomer has been successfully copolymerized
with styrene in a molar ratio of 50/50. I will try a living polymerization
to see what will happen.
d*****i
发帖数: 77
12
带thio的Macro chain transfer agent (如P4VP-CTA)加AIBN和monomer(如styrene)
能用RAFT合成纯P4VP-co-PS 的block copolymer吗?没做过RAFT。不过从机理来看理论
上应该会有一半是PS 的homopolymer啊!
不知我是否理解有误。请大侠指教!
拜谢!
z*****y
发帖数: 7
13
Hi,
Does anyone know if ketone containing monomers are compatible with radical
polymerization? Some people told me ketone is not stable when radical
polymerizatios are performed.
Appreciate any of your ideas.
p*****r
发帖数: 75
14
来自主题: Macromolecules版 - Monomer purification for ATRP (转载)
【 以下文字转载自 Chemistry 讨论区 】
发信人: poylmer (your home is where your heart is), 信区: Chemistry
标 题: Monomer purification for ATRP
发信站: BBS 未名空间站 (Sun Feb 3 22:32:38 2013, 美东)
Can anyone share how to purify styrene, methyl acrylate and acrylonitrile,
purchased from Aldrich, for ATRP? This is my first time to play with this
type of reactions. Thanks
x*****l
发帖数: 137
15
来自主题: Macromolecules版 - Monomer purification for ATRP (转载)
这个没必要吧?ATRP水相里都在做
monomer过个碱性氧化铝的柱子就行了,然后放冰箱里没问题的
i********e
发帖数: 50
16
来自主题: Biology版 - 请教native page

faction,然后用这些fraction做western blot (注:这时候SDS-PAGE会让蛋白变性根
本就不重要,你只是要确定自己的蛋白是在哪些fraction里面)。gel filtration的每
个fraction根据和standard蛋白位置的比较,是可以知道大概的size的,那不就知道你
的protein的size了吗。你已知monomer是550Kda,到时候不就知道是monomer还是
tetramer了吗
我们的tetramer就是用gel filtration 分离纯化出来的,western 的结果也没问题。
现在怀疑monomer的存在。SDS-PAGE的话,假如原本是tetramer的蛋白也会变性成
monomer跑出来。这样就不知道原来fraction里的究竟是tetramer还是mononer.这就是
我为什么想用native-page的原因。monomer就有550Kda,一般gel filtration用的
standard 蛋白没有那么大的。最理想的结果是tetrmer在void volume,monomer不是。
用什么柱子能使2者的re
d********y
发帖数: 176
17
http://onlinelibrary.wiley.com/doi/10.1002/masy.19910420119/pdf
Article
Inhibiting or cocatalytic effect of water and other additives on cationic
polymerization of cyclodimethylsiloxanes
Authors
P. Sigwalt,
C. Gobin,
P. Nicol,
M. Moreau,
M. Masure
First published: March 1991Full publication history
DOI: 10.1002/masy.19910420119View/save citation
Cited by: 14 articlesCitation tools
Funding Information
Abstract
Cyclodimethylsiloxanes such as hexamethylcyclotrisiloxane (D3) and
octamethyl-cyclotetr... 阅读全帖
b*o
发帖数: 47
18
来自主题: Macromolecules版 - 一个高分子科学的基本问题
How about this picture of polymer conformations?
First, we define "the unperturbed state" of polymer chains as the state only
short-range interactions among monomers are considered (such as bond angles
and bond rotation angles) but no consideration of the interaction potential
between non-bonded monomers. At this state, if we take several connected real
monomers as a step of random walk (to make ri*rj=0 for i not = j), i.e.,
rw-monomer. Then, the volume of each of these rw-monomer is not fully
o
i********e
发帖数: 50
19
来自主题: Biology版 - 请教native page
有个超大蛋白,单体为550Kda, 细胞里是tetramer。想看一下转基因表达后的状态,是
monomer/dimer/tetramer.请问除了native page还有什么方法能够鉴别或者比较
monomer/tetramer?
native page用了basic-native gel protocol。做western blot的话,使用的抗体和
monomer或tetramer结合的效果会有差异吗?比如monomer的结合效果好,band清晰。抗
体和tetramer 反应弱,看不大出来band?
比较奇怪的是,6%的胶跑3个小时和6个小时的结果不一样。难道6个小时后所有的蛋白
跑出去了?不应该啊.
求高人指点。
d********y
发帖数: 176
20
来自主题: Chemistry版 - paper help. Thanks!
https://goo.gl/KBNM3R
DOI:10.1039/J19710001136
Citation:J. Chem. Soc. A, 1971,0, 1136-1138
Issue 0, 1971
From the journal:
Journal of the Chemical Society A: Inorganic, Physical, Theoretical
A gas-phase Raman study of trimethylaluminium and trimethylboron monomers
R. J. O'Brien and G. A. Ozin
Abstract
Gas-phase Raman data are reported for trimethylaluminium. The dimer–monomer
equilibrium which exists in the vapour phase was observed over the
temperature range 70–290°C and from these data, band... 阅读全帖
b*o
发帖数: 47
21
来自主题: Macromolecules版 - 生物和高分子,请大家畅所欲言
As I understand, current polymer theories basically start from athermal
system, and then modify with the consideration of monomer-monomer (or
monomer-solvent) interactions. What I meant in the previous one is, in
heterogeenous polymers such as protein, it might be better to start from
considering both monomer/monmomer interaction and chain conectivity. What do
you think?
在 Bio (Polymer) 的大作中提到: 】
basics:
framework
b*o
发帖数: 47
22
来自主题: Macromolecules版 - 一个高分子科学的基本问题
Good discussion and it is becoming more interesting. The two premises you
pointed out are really my assumptions. Here we need to differentiate what we
mean by monomers in polymer physics and the real chemical monomers. If we take
the chemical sense, the monomer is not a kai=0 solvent for the corresponding
polymer, i.e., PS in styrene. In the physics sense, the monomer in the test
polymer should not be able to differentiate, in the aspect of nearest
neighbour interaction enthalpy sense, if its no
h*****y
发帖数: 366
23
来自主题: Macromolecules版 - 请问一个关于高分子的问题,不胜感激.
谢谢,我没有教科书.
你所指的每一个分子是monomer吗?
就是说把monomer当成一个整体,每一个monomer在溶液中的位置都是变化的,每个
monomer之间又是靠化学键连接起来的.这就是所谓的random coil 吗?
既然是random coil, 质心该如何确定呢?难道不论怎么random, 高分子在溶液中还是基
本像圆(或是球体)一样?但是,就像您说得,polymer可以像僵硬的绳子一样是直的.是不
是说在这样的情况下,质心就是绳子的中点?
如果是其他的形状,那么就是几何中心?
不知道我这样的理解是否正确呢?
d**a
发帖数: 3715
24
I recently synthesized a monomer with a styrene as one functional end group
(confirmed by NMR) and try to co-polymerize this monomer with commercially
available styrene
I ran the reaction in this way:
mix my monomer A, styrene, and AIBN in tolunene
A: 0.25 g, 0.48 mmol
styrene: 0.05 g, 0.48 mmol
AIBN 0.0055 g, 0.034 mmol, 3.5 mol% of monomers.
Freeze-thaw degas twice,nitrogen purge, in 50 mL of toluene at 80 degree C,
stirring for three days.
But it came out nothing has happened. I just checked
a*****a
发帖数: 210
25
来自主题: Macromolecules版 - Copolymer问题请教
alternation/alternative polymerization.
mostly depends on monomers. Ideally,radical of one monomer prefers the
molecule of the other monomer not itself. one example is allyl monomer and
maleic double bond.
s********l
发帖数: 1195
26
来自主题: Biology版 - 求推荐计算晶体结构rmsd的软件
我不是做结晶的,最近拿到一个蛋白结构,一个晶格里面有四个monomer,每个monomer
的氨基酸序列是一样的,但是四个chain的conformation不完全一致,其中A和C对称,B
和D对称。
现在想要通过计算每两个chain之间的backbone和sidechain的rmsd来定量地说明A和C
identical,B和D identical
请问该如何计算呢?有什么软件推荐的?
我看到有FATCAT,Mammoth,Dali,还有其他一些,一点概念都没有,不知道用哪个好
,请专家指点下。
另外,看到大部分软件需要upload要比较的两个结构,我只有一个tetramer的pdb file
,怎么把单独的monomer存成一个新的pdb file呢?我知道该怎么用pymol去掉其他的
chain,但是每次都只能存成新的session,而不是新的pdb,这个有什么trick呢?
多谢!
i********e
发帖数: 50
27
来自主题: Biology版 - 请教native page

有抗体,western 没问题。问题是要鉴别是monomer还是tetramer.SDS-PAGE是变性蛋白
,出来的都是monomer了。实验目的是确定蛋白的状态,目前只想到native page 和gel
filtration.
谢谢你关于柱子的建议,打算试一下。可是出来的fraction还是需要别的方法来确定到
底是monomer或tetramer吧。就算出来2个peak,怎么能说是2种不同状态呢?
l**********1
发帖数: 5204
28
需要genome 生统的背景
比如 H 大 以下 两lab (NB: one now is at Stanford)
//biosun1.harvard.edu/complab/
的至少one first author a paper 那样的背景
sunny 再去修个MD 如何
one mentor:
//www.hsph.harvard.edu/faculty/frank-hu/
cited from last week Cell cover article:
pp393
>With respect to the first question, replication initiation occurs
>as DnaA protein monomers bind or unbind stochastically and
cooperatively to form a multimeric complex at the replication
origin (Figure 4B, top) (Browning et al., 2004). When the complex
is c... 阅读全帖
d*****s
发帖数: 647
29
来自主题: Biology版 - 怎么证明一个protein是dimer?
我们以前做过eNOS的dimer和monomer,程序如下:
正常提取蛋白,按照常规Western Blot准备标本
将标本分为2份:一份boiled,一份unboiled
在4度下跑SDS-PAGE胶
然后Western blot程序
最好在胶片上判断:Boiled的标本只有1条monomer带,unboiled的标本在2倍monomer分
子量位
置有条带表示是dimer
k****o
发帖数: 728
30
来自主题: Chemistry版 - Copolymer 问题请教
正在写一篇论文,需要讨论一下关于copolymer里不同repeating unit alternative排
列的问题。比如copolymer为了达到两种monomer 1:1间隔排列,应该要控制monomer的
比例吧,但未必就是1:1投料,因为反应性不同。再就是不同monomer聚在一起未必就是
严格的ABABABAB间隔排列,应该也会AAABABAABBABAABA这样不规则。我就想找一下
论述这方面的paper,最好是review,但查不到。谁知不知道这方面文献?多谢!
d****n
发帖数: 397
31
来自主题: Chemistry版 - gas phase nucleation问题求教 (转载)
【 以下文字转载自 Physics 讨论区 】
发信人: dragon (dragon), 信区: Physics
标 题: gas phase nucleation问题求教
发信站: BBS 未名空间站 (Sat Mar 16 00:45:57 2013, 美东)
版上大牛,
我有个问题。就是gas phase nucleation.我们都知道pure water在0度以下,-40度
以上是不会结冰的。这是因为要形成冰核,必需翻越一个能垒。这个能垒联接了过冷水
(metastable state)和冰(stable state).同样也有过热蒸汽。当一个gas phase
species的浓度大于它的饱和蒸汽压的时候,它也不会形成droplet。所以nucleation(
形成droplet的过程),也是有个能垒。这个能垒和nucleation 速率有关,就是物理化学
(化学物理)里面的transition state theory.这个nucleation rate很早就已经有人
研究,Gibbs就提出classical nucleation theory.这个理论后来被发... 阅读全帖
d********y
发帖数: 176
32
http://onlinelibrary.wiley.com/doi/10.1002/masy.19900320118/pdf
On the nature of active species in cationic ring-opening polymerization of
cyclodimethylsiloxanes
Authors
Pierre Sigwalt,
Vivian Stannett
First published: February 1990Full publication history
DOI: 10.1002/masy.19900320118View/save citation
Cited by: 5 articlesCitation tools
Abstract
Contrarily to cationic ring-opening polymerization of cyclic ethers and of
some other cyclic monomers, for which direct identification of the various
t... 阅读全帖
w********h
发帖数: 12367
33
来自主题: Macromolecules版 - 一个高分子科学的基本问题
thanks for your further clarification.
as to monomer slovents (here it just means the small molecular weight solvents
generally), they can be good, theta, poor, or even non-solvents.
if it means the exactly the monomer of the solute polymer chain,
generally we think it is good solvent.
the thing is:
when the solvent chain (or matrix chain) changes from a monomer to a polymer
chain as the solute chain, what happens there?
Good---->theta---->all theta to polymer in itself?

take
a
a
was
this
as
ch
s*****o
发帖数: 65
34
来自主题: Macromolecules版 - Help! interview this morning
It is true. The reaction of end group with initiator is very critical to the
polymer property. They have trouble on this now. So they also ask me study
stability.
Frictionate means to seperate it. I am think the end group may be seprated
from monomer by GPC. I am not sure too.
Two batches of monomer maybe means that they used different methods to make
it. I was surprised too. I asked two time. They told me two batch monomer are
really different.

they
because
like an
looks
email them
fractions.
c*****e
发帖数: 238
35






This is a good but unanswered question. If the bonding is permanent and you
are using monomer with multiple functional group, then gelation should always
happen as a result of percolation. If you have bi-functionalized monomers, the
number fraction of multiple functionalized monomers has to exceed some
critical ratio for percolation to occur. If the reaction rate is slow, my
expectation is that gelation will occur as the percolation process is fairly
well represented by the mean field
y***e
发帖数: 6082
36
来自主题: Macromolecules版 - 谁在做ATRP啊?
ATRP没啥前途的,RAFT对单体相对来说就好多了,可惜又对CTA选择性太强,总之活性
聚合要走的路还很长

why? because of the extreme large of the monomer? I tried some ATRP on my
synthesized monomer, it failed, too. but the reason is very likely because
the size of the monomer which cuase some steric difficulties.
s****e
发帖数: 2934
37
来自主题: Macromolecules版 - [合集] 谁在做ATRP啊?
☆─────────────────────────────────────☆
cds (红毛呼呼猪) 于 (Sat Sep 9 13:15:25 2006) 提到:
大家认识一下阿
☆─────────────────────────────────────☆
yueke (小鱼儿) 于 (Wed Sep 20 11:58:05 2006) 提到:
ATRP没啥前途的,RAFT对单体相对来说就好多了,可惜又对CTA选择性太强,总之活性
聚合要走的路还很长

why? because of the extreme large of the monomer? I tried some ATRP on my
synthesized monomer, it failed, too. but the reason is very likely because
the size of the monomer which cuase some steric difficulties.
☆─────────────────────────────────────☆
hu
p******4
发帖数: 38
38
来自主题: Macromolecules版 - Help on PVP ATRP polymerization
The problem may be in the monomer. Normally it has the inhibitor in the
vinyl monomers. So it is necessary to purify the monomer from the inhibitor
before the polymerization.
Otherwise email the corresponding author and tell him/her your problem. In
most cases he/she will contact you soon.
Good luck,
k****o
发帖数: 728
39
来自主题: Macromolecules版 - Copolymer问题请教
正在写一篇论文,需要讨论一下关于copolymer里不同repeating unit alternative排
列的问题。比如copolymer为了达到两种monomer 1:1间隔排列,应该要控制monomer的
比例吧,但未必就是1:1投料,因为反应性不同。再就是不同monomer聚在一起未必就是
严格的ABABABAB间隔排列,应该也会AAABABAABBABAABA这样不规则。我就想找一下论述这方面的paper,最好是review,但查不到。谁知不知道这方面文献?多谢!
k****o
发帖数: 728
40
来自主题: Macromolecules版 - Copolymer问题请教
正在写一篇论文,需要讨论一下关于copolymer里不同repeating unit alternative排
列的问题。比如copolymer为了达到两种monomer 1:1间隔排列,应该要控制monomer的
比例吧,但未必就是1:1投料,因为反应性不同。再就是不同monomer聚在一起未必就是
严格的ABABABAB间隔排列,应该也会AAABABAABBABAABA这样不规则。我就想找一下论述这方面的paper,最好是review,但查不到。谁知不知道这方面文献?多谢!
d****n
发帖数: 397
41
来自主题: Physics版 - gas phase nucleation问题求教
版上大牛,
我有个问题。就是gas phase nucleation.我们都知道pure water在0度以下,-40度
以上是不会结冰的。这是因为要形成冰核,必需翻越一个能垒。这个能垒联接了过冷水
(metastable state)和冰(stable state).同样也有过热蒸汽。当一个gas phase
species的浓度大于它的饱和蒸汽压的时候,它也不会形成droplet。所以nucleation(
形成droplet的过程),也是有个能垒。这个能垒和nucleation 速率有关,就是物理化学
(化学物理)里面的transition state theory.这个nucleation rate很早就已经有人
研究,Gibbs就提出classical nucleation theory.这个理论后来被发展到
multicomponent很复杂的公式。但是这个理论有个不好的地方是(1)它要surface
tension.这是一个宏观量,当droplet很小的时候不一定准。(2)当supersaturation
接近spinodal decomposition的时候,能垒... 阅读全帖
d***l
发帖数: 129
42
Real-space imaging of interfacial water with submolecular resolution
Abstract
Water/solid interfaces are vital to our daily lives and are also a central
theme across an incredibly wide range of scientific disciplines. Resolving
the internal structure, that is, the O–H directionality, of water molecules
adsorbed on solid surfaces has been one of the key issues of water science
yet it remains challenging. Using a low-temperature scanning tunnelling
microscope, we report submolecular-resolution ima... 阅读全帖
S*********g
发帖数: 24893
43
【 以下文字转载自 Stock 讨论区 】
发信人: StephenKing (金博士), 信区: Stock
标 题: 向民族英雄包鹏程致敬!为民族英雄包鹏程欢呼!
发信站: BBS 未名空间站 (Wed Jun 3 20:54:21 2015, 美东)
Pengcheng Bao, Graduate Student
Pengcheng is a second year graduate student. He obtained his B.S. in physics
from Nankai Univeristy in China.
Project: Development of methodology for realistic modeling of heterogeneous
catalytic interfaces.
Tel: 310-206-3215
Email: [email protected]
/* */
PENGCHENG BAO
Education
and Awards
2009 –
NANKAI UNIVERSITY TIANJIN, CHINA... 阅读全帖
R*********e
发帖数: 73
44
得到博士offer的本科生简历(挂网公开的,应该可以讨论把)在下面,先只请教下打动
发考题们给了博士offer的原因,别的不八卦:)哈哈
照说本科生得让发考题们认为极其有科研的潜质,才能打败无数硕士生,发考题们才
会直接给本科生offer直攻博士;
看这份简历,我的感觉是
1.本科成绩好,会读书
2.参加了很多国内老师的项目,参加了一些海外老师的暑期短期项目,有些学术锻炼和想
法,但无明显成果,可能人缘好,会来事;但不排除夸大自己作用的可能
3.得了一些奖学金,国内高校基本上成绩好加积极参加学校各项活动,对老师会来事,自
然就能得.
3.英语写的好
4.积极参加各种活动,精力充沛,勤奋,把自己的时间,安排的满满当当的,有废寝忘食的
倾向.
5.非常有计划性和目的性,经过几年奋斗,作为本科学生,已经达到面面聚到的无短板程
度.
作为本科生,这份简历无疑是优秀的;但是却无法直接得出极其有科研的潜质的结论;相
反无数硕士生申请攻博士,由于年龄大一些和工作经历,也许本科成绩绩点低一些,得的
奖学金项目少一些,但是有实践经验,多数还会有1-2篇海外(尽管可能级别和影响不高)
期刊发表的... 阅读全帖
S*********g
发帖数: 24893
45
Pengcheng Bao, Graduate Student
Pengcheng is a second year graduate student. He obtained his B.S. in physics
from Nankai Univeristy in China.
Project: Development of methodology for realistic modeling of heterogeneous
catalytic interfaces.
Tel: 310-206-3215
Email: [email protected]
/* */
PENGCHENG BAO
Education
and Awards
2009 –
NANKAI UNIVERSITY TIANJIN, CHINA
Bachelor of Science in Physics (Condensed Matter Physics), June 2013.
Academic Record:
2009-2010: Overall: 93.40 Ranking 1/141 Maj... 阅读全帖
S*********g
发帖数: 24893
46
【 以下文字转载自 Stock 讨论区 】
发信人: StephenKing (金博士), 信区: Stock
标 题: 向民族英雄包鹏程致敬!为民族英雄包鹏程欢呼!
发信站: BBS 未名空间站 (Wed Jun 3 20:54:21 2015, 美东)
Pengcheng Bao, Graduate Student
Pengcheng is a second year graduate student. He obtained his B.S. in physics
from Nankai Univeristy in China.
Project: Development of methodology for realistic modeling of heterogeneous
catalytic interfaces.
Tel: 310-206-3215
Email: [email protected]
/* */
PENGCHENG BAO
Education
and Awards
2009 –
NANKAI UNIVERSITY TIANJIN, CHINA... 阅读全帖
S*********g
发帖数: 24893
47
【 以下文字转载自 Stock 讨论区 】
发信人: StephenKing (金博士), 信区: Stock
标 题: 向民族英雄包鹏程致敬!为民族英雄包鹏程欢呼!
发信站: BBS 未名空间站 (Wed Jun 3 20:54:21 2015, 美东)
Pengcheng Bao, Graduate Student
Pengcheng is a second year graduate student. He obtained his B.S. in physics
from Nankai Univeristy in China.
Project: Development of methodology for realistic modeling of heterogeneous
catalytic interfaces.
Tel: 310-206-3215
Email: [email protected]
/* */
PENGCHENG BAO
Education
and Awards
2009 –
NANKAI UNIVERSITY TIANJIN, CHINA... 阅读全帖
R******d
发帖数: 5739
48
来自主题: Belief版 - 进化论的错误假设 (转载)
Let me rephrase my words.
All the biological process have to abide the law of chemistry.
It does not matter what the origin of a biological process or how it began,
you can say RNA, protein, sugar, or whatever. You get to explain how these
molecules formed in nature in the first place.
Please do not just Wiki some topic, and then post it here because a lot of
them have erroneous messages. The belowing so call "well-known" Miller
experiment did not reproduce the samwe amino acids in our body.
--... 阅读全帖
g*********y
发帖数: 123
49
来自主题: TrustInJesus版 - 基督,外星人,意识,和暗物质
"说一些东西的时候不要想当然" 太对了.
我在搞交叉学科之前和你想得差不多, 但其实劲不起细想. 比如,上面有人已经指出,
只有蛋白或rna的东西往往是寄生,那你哪来的主体?
是,我是不知道原始汤中有什么东西,但我知道形成一般意义上的生命需要什么东西 -
- 核酸,氨基酸,是,浓度我也不知道,可是我知道这些东西都是有离解常数的,如果
浓度很高(比如像楼上那位的汤),这些东西离解会大于合成的(艾滋病毒没有dna,
可在室温下不到24小时就离解了,这就是为什么一般人不会轻易得艾滋病的原因)。而
分子多聚物的浓度是随级数呈指数递减的, 即,如果反应常数相同,假如dimer的浓度
是monomer的一半,那tetramer的浓度就只有monomer的1/4,这样下去,即使形成生命只
需要30mer, 你可以想象一下单体的浓度得多大,可能真得像楼上那位的汤。这样浓度
的原始汤如果不是想当然,应该不存在的。
更何况,生命还需要,30mer RnA(or DNA) + 30mer (protein) + 合适的三级结构,如
果不是想当然,你必须承认 -- 难,这真是很难。
简单一点,细胞里一切都是
W*********e
发帖数: 247
50
来自主题: Biology版 - 求推荐计算晶体结构rmsd的软件
用notepad打开pdb文件, 删掉不需要的monomer的坐标, 另存一下就行了

monomer
,B
file
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