Nadph q - USMLE Forums
USMLE Forums Logo
USMLE Forums         Your Reliable USMLE Online Community     Members     Posts
Home
USMLE Articles
USMLE News
USMLE Polls
USMLE Books
USMLE Apps
Go Back   USMLE Forums > USMLE Step 1 Forum

USMLE Step 1 Forum USMLE Step 1 Discussion Forum: Let's talk about anything related to USMLE Step 1 exam


Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 09-15-2012
venky2600's Avatar
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,186
Threads: 119
Thanked 822 Times in 434 Posts
Reputation: 832
Send a message via Yahoo to venky2600
Question Nadph q

Q) NADPH is the most important for many biosynthetic pathways...which is the enzyme that is involved in formation of NADPH?

a) pyruvate dehydrogenase
b) transketolase
c) fructose-6-bisphosphatase
d) malate dehydrogenase
e) arginase
f) fatty acyl coa synthase
g) glutamate dehydrogenase
Reply With Quote Quick reply to this message



  #2  
Old 09-15-2012
blade's Avatar
USMLE Forums Guru
 
Steps History: 1+CK+CS+3
Posts: 358
Threads: 22
Thanked 204 Times in 116 Posts
Reputation: 214
Default BB?

Quote:
Originally Posted by venky2600 View Post
Q) NADPH is the most important for many biosynthetic pathways...which is the enzyme that is involved in formation of NADPH?

a) pyruvate dehydrogenase
b) transketolase
c) fructose-6-bisphosphatase
d) malate dehydrogenase
e) arginase
f) fatty acyl coa synthase
BB?
NADPH is produced in HMP pathway by G6PD
Transketolase is involved in the pathway but not? involved in NADPH production directly
__________________
with God,nothing is impossible...PREMATCHED!!!
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Reply With Quote Quick reply to this message
  #3  
Old 09-15-2012
USMLE Forums Guru
 
Steps History: 1+CK+CS
Posts: 307
Threads: 36
Thanked 127 Times in 61 Posts
Reputation: 137
Default

D? Malate dehydrogenase?
Reply With Quote Quick reply to this message
 
  #4  
Old 09-15-2012
USMLE Forums Scout
 
Steps History: Not yet
Posts: 92
Threads: 9
Thanked 22 Times in 16 Posts
Reputation: 32
Default Malae dehydrogenase

NADPH synthesised in two pathways:

1.HMP shunt

2.Malic enzyme which converts malate to pyruvate
Reply With Quote Quick reply to this message
  #5  
Old 09-15-2012
step1success's Avatar
USMLE Forums Scout
 
Steps History: Step 1 Only
Posts: 28
Threads: 2
Thanked 5 Times in 2 Posts
Reputation: 15
Question

Quote:
Originally Posted by venky2600 View Post
Q) NADPH is the most important for many biosynthetic pathways...which is the enzyme that is involved in formation of NADPH?

a) pyruvate dehydrogenase
b) transketolase
c) fructose-6-bisphosphatase
d) malate dehydrogenase
e) arginase
f) fatty acyl coa synthase
g) glutamate dehydrogenase
.choice F....B-oxidation.
Reply With Quote Quick reply to this message
  #6  
Old 09-15-2012
koolkiller88's Avatar
USMLE Forums Master
 
Steps History: Step 1 Only
Posts: 864
Threads: 62
Thanked 374 Times in 225 Posts
Reputation: 384
Default

Quote:
Originally Posted by venky2600 View Post
Q) NADPH is the most important for many biosynthetic pathways...which is the enzyme that is involved in formation of NADPH?

a) pyruvate dehydrogenase NADH production
b) transketolase
c) fructose-6-bisphosphatase
d) malate dehydrogenase NADH production
e) arginase urea synthesis
f) fatty acyl coa synthase
g) glutamate dehydrogenase
my bet on transketolase but i am still not convinced as
NADPH production take place by
1. G6PD in HMP shunt
2. Malic enzymes in fatty acid synthesis
__________________
One day i will infect these microbes and they will search for "Anti-MEbiotic"....
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Quick reply to this message
  #7  
Old 09-15-2012
venky2600's Avatar
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,186
Threads: 119
Thanked 822 Times in 434 Posts
Reputation: 832
Send a message via Yahoo to venky2600
Post

Quote:
Originally Posted by koolkiller88 View Post
my bet on transketolase but i am still not convinced as
NADPH production take place by
1. G6PD in HMP shunt
2. Malic enzymes in fatty acid synthesis
so, what's your answer finally..?
Reply With Quote Quick reply to this message
  #8  
Old 09-15-2012
koolkiller88's Avatar
USMLE Forums Master
 
Steps History: Step 1 Only
Posts: 864
Threads: 62
Thanked 374 Times in 225 Posts
Reputation: 384
Default

Quote:
Originally Posted by venky2600 View Post
so, what's your answer finally..?
Ok finally i would go with f) fatty acyl coa synthase
__________________
One day i will infect these microbes and they will search for "Anti-MEbiotic"....
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Quick reply to this message
  #9  
Old 09-15-2012
USMLE Forums Scout
 
Steps History: 1+CK+CS
Posts: 32
Threads: 8
Thanked 10 Times in 8 Posts
Reputation: 20
Send a message via Skype™ to samiaaleem
Default

Malate Dehydrogenase?
Reply With Quote Quick reply to this message
  #10  
Old 09-16-2012
USMLE Forums Master
 
Steps History: 1+CK+CS
Posts: 1,039
Threads: 189
Thanked 570 Times in 323 Posts
Reputation: 580
Default my answer :)

d) malate dehydrogenase
Reply With Quote Quick reply to this message
  #11  
Old 09-16-2012
venky2600's Avatar
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,186
Threads: 119
Thanked 822 Times in 434 Posts
Reputation: 832
Send a message via Yahoo to venky2600
Correct Answer D is right

the correct answer is D) malate dehydrogenase(malic enzyme)

NADPH is used for many biosynthetic pathways..it is formed mainly from HMP shunt via glucose-6-phosphate dehydrogenase and phosphogluconate dehydrogenase...these two enzymes forms NADPH in HMP(pentose pathway )....apart from this ,during fatty acid synthesis NADPH is produced from another enzyme--malate dehydrogenase in cytosol

in mitochondria--------acetylcoA+ OAA------>citrate

citrate shuttles to cytosol and again degrades via citrate lyase to acetyl coA and OAA

acetuly coA is used for fatty acid synthesis by forming malonyl co A

whereas OAA--------> malate------------> pyruvate by malate dehydrogenase which also releases NADPH as the source

a) pyruvate dehydrogenase--------it is used for synthesis of pyruvate
b) transketolase-------
it synthesize ribose 5 phosphate
c) fructose-6-bisphosphatase-------
it is used for gluconeogenesis for irreversible step of glycolysis forming fructose 6 phosphate
e) arginase-------
it is used in urea cycle for synthesizing urea
f) fatty acyl coa synthase--------
it is a complex that synthesize fatty acids..nothing to do with NADPH
g) glutamate dehydrogenase
--------it is used in urea cycle as nitrogen donor for urea synthesis
Reply With Quote Quick reply to this message
The above post was thanked by:
tai35 (09-21-2012)



Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the USMLE Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Medical School
Choose "---" if you don't want to tell. AMG for US & Canadian medical schools. IMG for all other medical schools.
USMLE Steps History
What steps finished! Example: 1+CK+CS+3 = Passed Step 1, Step 2 CK, Step 2 CS, and Step 3.

Choose "---" if you don't want to tell.

Favorite USMLE Books
What USMLE books you really think are useful. Leave blank if you don't want to tell.
Location
Where you live. Leave blank if you don't want to tell.

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
NADPH Oxidase and Atherosclerosis! slowpoke USMLE Step 1 Forum 3 05-14-2012 04:08 AM

RSS Feed
Find Us on Facebook
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

USMLE® & other trade marks belong to their respective owners, read full disclaimer
USMLE Forums created under Creative Commons 3.0 License. (2009-2014)