Billy Preston, the keyboardist who was dubbed "the Fifth Beatle" after his late-'60s stint accompanying the group, died Tuesday (June 6) at age 59 following a lengthy illness.

According to The Associated Press, Preston had been in a coma since last November as a result of kidney failure stemming from malignant hypertension. He died in a hospital in Scottsdale, Arizona, where he had lived for the past few years.

A child prodigy, Preston spent his teenage years touring and/or recording with a host of acts, including gospel star Mahalia Jackson, soul legend Sam Cooke and rock pioneer Little Richard. It was while on tour with Richard that Preston first met the Beatles, and within a few years he was accompanying the group in the studio, playing keyboards and singing backing vocals on the band's final three albums, The White Album, Abbey Road and Let It Be (and earning him a nickname he'd carry with him for the rest of his days). On the latter album, he performed with the group during its brief-but-famous rooftop concert: the Beatles' final public performance. During the 1970s, he fulfilled a similar role with the Rolling Stones, playing on several of their albums and taking a prominent role in the band's live shows; he also contributed to the group's 1997 LP, Bridges to Babylon.

In a career that spanned five decades, Preston brought his immensely soulful keyboard work and singing to albums by Bob Dylan, Aretha Franklin, George Harrison, John Lennon, Sly and the Family Stone, Al Green, Ray Charles, Elton John, Eric Clapton, Luther Vandross, Quincy Jones and Joni Mitchell, among many others. In recent years he was frequently called upon by producer Rick Rubin, contributing to albums by Johnny Cash, Neil Diamond, Macy Gray and the Red Hot Chili Peppers; although very ill at the time, he performed on the latter group's recent album, Stadium Arcadium.

Preston also had a successful solo career (he was the first act signed to the Beatles' Apple Records), scoring several hits in the 70s, including "Nothing From Nothing" and "Will It Go Round in Circles." He also co-wrote "You Are So Beautiful to Me," which Joe Cocker turned into an international smash.

Preston went through a rough patch in the '80s and '90s, running into legal trouble on drug charges, insurance fraud and probation violations.

Preston continued performing until he fell ill last year. In 2005, he appeared on the season finale of "American Idol," performing his single "With You I'm Born Again" with Vonzell Solomon.