DNA sequences that code for proteins need to convey, in addition to the protein-coding information, several different signals at the same time. These "parallel codes" include binding sequences for regulatory and structural proteins, signals for splicing, and RNA secondary structure. Here, we show that the universal genetic code can efficiently carry arbitrary parallel codes much better than the...

Convolutional codes over rings have been motivated by phase-modulated signals. Some structural properties of the generator matrices of such codes are presented. Successively stronger notions of invertibility of generator matrices are studied, and a new condition for a convolutional code over a ring to be systematic is given and shown to be equivalent to a condition given by Massey and Mittelhol...

Let $\mathbb{F}_p$ be a finite field and $u$ be an indeterminate. This article studies $(1-2u^k)$-constacyclic codes over the ring $\mathcal{R}=\mathbb{F}_p+u\mathbb{F}_p+u^2\mathbb{F}_p+u^{3}\mathbb{F}_{p}+\cdots+u^{k}\mathbb{F}_{p}$ where $u^{k+1}=u$. We illustrate the generator polynomials and investigate the structural properties of these codes via decomposition theorem.

Abstract We study the structure of constacyclic codes of length ps over the ring Fpk + uFpk + · · · + um−1Fpk in terms of ideals in the quotient ring (Fpk + uFpk + · · · + um−1Fpk)[x]/〈xp s − λ〉, where λ is a unit element in Fpk + uFpk + · · · + um−1Fpk . In particular, we complete a structural classification of constacyclic codes of length ps over Fpk + uFpk and determine their minimum Hamming...

Protein folding codes embodying local interactions including surface and secondary structure propensities and residue-residue contacts are optimized for a set of training proteins by using spin-glass theory. A screening method based on these codes correctly matches the structure of a set of test proteins with proteins of similar topology with 100% accuracy, even with limited sequence similarity...

Rotavirus, the leading cause of infantile gastroenteritis, with nearly a million deaths worldwide every year, has a spherical shape with many spikes that bind firmly to a host cell. The virus is composed of six structural proteins arranged in three concentric layers, which enclose the viral genome consisting of 11 doublestranded RNA (dsRNA) segments. Each segment codes for at least one protein,...

By recombination between bacteriophage T4 wh2, a dihydrofolate reductaseless mutant, and T6, I have prepared T4 wh(T6), a T4 strain which codes for the T6-specific soluble dihydrofolate reductase. This strain has the heat sensitivity of T6, not T4, which provides direct evidence that the wh gene codes for both the soluble dihydrofolate reductase and the structural dihydrofolate reductase which ...