Problem 2513. Genome decoding

Inspired by a question on the answer forum:

You are given a matrix of 8-bit integers which encodes a genome. Each integer can be converted into a sequence by converting it first to binary and then converting bit pairs using the rule A = 00, C = 01, T = 10, G = 11. For example, 177 -> 10110001 -> TGAC.

Convert the matrix into a cell array of sequences.

str2num and regexp not allowed.