SNG 6max 0.25€ AKs vs donk bet river

PokerStars - 15/30 Ante 4 NL (6 max) - Holdem - 4 players
Hand converted by PokerTracker 4

Hero (BTN): 76.33 BB
SB: 34.9 BB (VPIP: 44.44, PFR: 16.67, 3Bet Preflop: 0.00, Hands: 18)
BB: 61.7 BB (VPIP: 23.06, PFR: 14.92, 3Bet Preflop: 9.38, Hands: 416)
CO: 127.07 BB (VPIP: 22.27, PFR: 14.81, 3Bet Preflop: 6.45, Hands: 256)

4 players post ante of 0.13 BB, SB posts SB 0.5 BB, BB posts BB 1 BB

Pre Flop: (pot: 2.03 BB) Hero has A♦ K♦

fold, Hero raises to 2.5 BB, SB calls 2 BB, fold

Flop: (6.53 BB, 2 players) K♠ T♠ 7♥
SB checks, Hero bets 4.37 BB, SB calls 4.37 BB

Turn: (15.27 BB, 2 players) 6♦
SB checks, Hero bets 10.17 BB, SB calls 10.17 BB

River: (35.6 BB, 2 players) Q♠
SB bets 17.73 BB and is all-in, Hero ??

So what can i do in this case, i think i have to bet big to protect my hand flop and turn but when he donks river the rest of his chips can i fold my hand?

Cumps