Get an internal object from a nested object in Chrome storage

Question

I have a JavaScript type object in chromatic local storage

var obj = { 
    settings: {
        b : {
            e: 2
       },

       c: {
           d: 3 
       },

       ...
    }
}

The object objhas many internal objects. Now my goal is to access the attribute of the eobject band change it. I tried the easiest way: selecting everything objwith chrome.storage.local.get('settings'), and then changing the value obj.settings.b.eand save it. Since the size objcan be very large, I do not want to retrieve the entire object in memory. Are there any official means (preferably) or hack access to internal objects in the structure of nested objects?