Perhaps this walk throughwill help you. - It was one of the first I found after googling “edit output style”.
It looks like Biochemistry using a different reference format for Rapid Reports and for regular papers. Which are you looking for. The only obvious difference between the most recently available Biochemistry output style template, was that they want a trailing comma after the Author list in the bibliography, and not a full stop.
In Endnote, you can retrieve this Sep 2012 updated Biochemistry output style, by going to Endnote’s Help menu, selecting Web styles finder… Contains “Biochemistry”, looking for it in the list and downloading it, which will open it in Endnote. Here you can make any changes you need (like changing the bibliography templates so a comma rather than a full stop follows the word “Author” in each of them, and then “save as” (using the Endnote program) to a new name. Then in your word document, you need to change the output style template on the word ribbon to this newly named file.
The Forums are still not allowing the attachment of endnote output styles, so I can’t attach the one I created.
If you wanted the rapid report style, then you need to further edit the template to separate the authors with semi-colons rather than with commas in the Author lists part of the bibliography options. Don’t forget to keep the trailing space… I didn’t look further for other changes…
BTW, Biochemistry also have Word templates they suggest (or demand in the case of Rapid Reports) that you use.