Only moderators can initiate new posts. Anyone can add a comment to an existing post, but the comment should be related. So this entry is for general comments not related to any of the articles. Also for instructions to new users.
4 comments:
Anonymous
said...
Instructions: To leave a comment for any post, click the "comments" link at the bottom and you get a text-window to enter your comment. You have three option for identity: 1. if you have a google or gmail account, log in and leave the comment as yourself. You will be able to come back and edit or delete your comment later. 2. check "other" and fill in any name you like. "Someone" is a good name if you want your message to be headed by "Someone said . . .". You can still put your name at the bottom of the post if you want to be identified, but there is no verification (someone else could also sign his comment as you). 3. Check "Anonymous" - is same as 2 except the name is prefilled as "Anonymous".
Pedant's note on the usage of "proximal" and "distal".
The use of these terms in describing architecture of Complex II and III has become very popular recently, but it is becoming clear that at least two different incompatible meanings are being understood by different authors.
These are originally anatomical terms, and describe distance from the center of the animal, or position along an extremitity. There is no need to say distal to what, or proximal to what, unless you are saying one object is more distal or proximal than another: The forearm is distal to the elbow, the elbow is proximal to the forearm. The terminology which describes the distal and proximal hemes, or Q-sites, of Complex II is compatible with this: clearly the center of mass is somewhere in the AB extrinsic domain, the proximal sites in the membrane are on the same side of the membrane, the distal sites are on the other side. Likewise the "distal" and "proximal" positions of the iron-sulfur cluster in Complex III follow this usage.
Another group of authors is using distal and proximal as substitutes for "far" and "near", and naturally they feel obliged to say (or to ask) "near/far to/from what?
A good test to see which meaning is being used is to reverse the relation. In the atomical sense, "A proximal to B" implies "B distal to A" (just as A north of B implies B south of A). If you feel that A is proximal to B but B is also proximal to A, you would probably be better off saying A is "close to", or "near" B.
What to use for a hyphenated adjective? The thumb-proximal finger is called . . . thumb-near finger . . . thumb-close finger . . . don't quite sound right.
Myoglobin has proximal and a distal histidines. Are they so called because the distal histidine is farther from the Iron (not directly bonded like the proximal one), or because the distal histidine is on the "distal" side of the heme, away from the center of mass of the protein? Isn't the heme cleft kind of perpendicular to the surface so that neither side would be distal?
4 comments:
Instructions: To leave a comment for any post, click the "comments" link at the bottom and you get a text-window to enter your comment. You have three option for identity:
1. if you have a google or gmail account, log in and leave the comment as yourself. You will be able to come back and edit or delete your comment later.
2. check "other" and fill in any name you like. "Someone" is a good name if you want your message to be headed by "Someone said . . .". You can still put your name at the bottom of the post if you want to be identified, but there is no verification (someone else could also sign his comment as you).
3. Check "Anonymous" - is same as 2 except the name is prefilled as "Anonymous".
Pedant's note on the usage of "proximal" and "distal".
The use of these terms in describing architecture of Complex II and III has become very popular recently, but it is becoming clear that at least two different incompatible meanings are being understood by different authors.
These are originally anatomical terms, and describe distance from the center of the animal, or position along an extremitity. There is no need to say distal to what, or proximal to what, unless you are saying one object is more distal or proximal than another: The forearm is distal to the elbow, the elbow is proximal to the forearm.
The terminology which describes the distal and proximal hemes, or Q-sites, of Complex II is compatible with this: clearly the center of mass is somewhere in the AB extrinsic domain, the proximal sites in the membrane are on the same side of the membrane, the distal sites are on the other side. Likewise the "distal" and "proximal" positions of the iron-sulfur cluster in Complex III follow this usage.
Another group of authors is using distal and proximal as substitutes for "far" and "near", and naturally they feel obliged to say (or to ask) "near/far to/from what?
A good test to see which meaning is being used is to reverse the relation. In the atomical sense, "A proximal to B" implies "B distal to A" (just as A north of B implies B south of A). If you feel that A is proximal to B but B is also proximal to A, you would probably be better off saying A is "close to", or "near" B.
What to use for a hyphenated adjective? The thumb-proximal finger is called . . .
thumb-near finger . . .
thumb-close finger . . .
don't quite sound right.
maybe "adjacent" or "neighboring"
Myoglobin has proximal and a distal histidines. Are they so called because the distal histidine is farther from the Iron (not directly bonded like the proximal one), or because the distal histidine is on the "distal" side of the heme, away from the center of mass of the protein? Isn't the heme cleft kind of perpendicular to the surface so that neither side would be distal?
Post a Comment