Is it a kind of Mutant?

One mutation helps lunch, while your wounds it is healing.
In the corporate world one helps you to ceiling.

One is part of a thing that is often sequential
Or is sometimes inspired, often thought presidential.

With its friend one can drive you to feelings of shame,
With friend's brother it gives you a feeling of fame.

One mutation is paramount to sweet acts of couplings,
Then, afterward, It will again hide your dumplings.

Dress

One mutation helps lunch, while your wounds it is healing.

This mutation is: ...ing
giving dressing, a sauce or similar for your lunch, or a bandage for a wound.

In the corporate world one helps you to ceiling.

This mutation is, perhaps, ...for success or ...coat, or power...
giving dress for success or dress coat or power dress, all the same idea of (wearing) attire intended to show that one holds an important position in business.

One is part of a thing that is often sequential
Or is sometimes inspired, often thought presidential.

With its friend one can drive you to feelings of shame,

Its friend is, perhaps, ...down -
To dress down someone could well evoke shame.

With friend's brother it gives you a feeling of fame.

Friend's brother is then ...up -
To dress up can make you feel more glamorous or more like someone famous.

One mutation is paramount to sweet acts of couplings,

This mutation is likely: un...
giving undress, an paramount step in paramours' couplings

Then, afterward, It will again hide your dumplings.

The original word, without any mutations, brings us back to dress -
letting you hide whatever sort of dumplings you've got on ya.

• I got the "dressing" part right, then, that's something. – F1Krazy Mar 22 '17 at 22:01

My understanding of the riddle is that

the answer is some specific word, and each of the "mutations" gives a definition/explanation of a word that is the same as the answer but with one letter changed.

Is this correct at least? If so, I have a partial solution, which is extremely unlikely to be right but please hear me out. I believe the answer is

the word rang. Each "mutated" clue that I've figured out is one letter away from rang.

"In the corporate world, one helps you to ceiling" could refer to a

rung, as in a rung on the corporate ladder.

"One is part of a thing that is often sequential" could refer to a

rank in an organizational chart/hierarchy.

"Sometimes inspired, often thought presidential" could refer to a

rant. Rants can be very passionate, and are frequently on the subject of politics, including (especially this year) presidents.

"One mutation is paramount to sweet acts of couplings" could refer to a

ring, which is always used to symbolize an act of coupling at a wedding.

Again, one in a million shot but I figured I'd throw it out there.

• Thank you for restoring my faith in the ranks of the riddle-solvers. I high-plus-one-your assertion. I'll readdress my question. Your think that this a specific word is thoughtful and thunk. I've rethunk it through and had its thouthfulness thinked through. – Chowzen Jun 27 '16 at 5:14

I may not be able to explain everything, but to me it is the word

digits

One is part of a thing that is often sequential

A digit is a part of a number series

In the corporate world one helps you to ceiling

In corporate world digits can take one high

With its friend one can drive you to feelings of shame

with (-)negative sign its bad i.e., you are in debt

With friend's brother it gives you a feeling of fame

With +(positive) you are rich

One mutation helps lunch, while your wounds it is healing.
In the corporate world one helps you to ceiling.

Dressing (salad dressing, 'dressings' for wounds, and 'dressing for success')

One mutation is paramount to sweet acts of couplings,

Could be "blessing" (in order to get married, you traditionally need to get the blessing of the father of the bride-to-be).

I don't know whether I'm going down the right path here...

Is it

A suit?

Because

You're more probable to rise up (figuratively towards the ceiling) in a corporate world with a proper suit.

And

Suits seem presidential and give a feeling of fame.

And

A man usually gets married (acts of couplings) in a suit.

• Hi, welcome to Puzzling! Could you add some spoilertags (use >! at the start of a paragraph) so that people don't see the answer accidentally without meaning to? – Rand al'Thor Mar 21 '17 at 23:30