• HOME
  • NEWS
  • EXPLORE
    • CAREER
      • Companies
      • Jobs
    • EVENTS
    • iGEM
      • News
      • Team
    • PHOTOS
    • VIDEO
    • WIKI
  • BLOG
  • COMMUNITY
    • FACEBOOK
    • INSTAGRAM
    • TWITTER
Tuesday, October 28, 2025
BIOENGINEER.ORG
No Result
View All Result
  • Login
  • HOME
  • NEWS
  • EXPLORE
    • CAREER
      • Companies
      • Jobs
        • Lecturer
        • PhD Studentship
        • Postdoc
        • Research Assistant
    • EVENTS
    • iGEM
      • News
      • Team
    • PHOTOS
    • VIDEO
    • WIKI
  • BLOG
  • COMMUNITY
    • FACEBOOK
    • INSTAGRAM
    • TWITTER
  • HOME
  • NEWS
  • EXPLORE
    • CAREER
      • Companies
      • Jobs
        • Lecturer
        • PhD Studentship
        • Postdoc
        • Research Assistant
    • EVENTS
    • iGEM
      • News
      • Team
    • PHOTOS
    • VIDEO
    • WIKI
  • BLOG
  • COMMUNITY
    • FACEBOOK
    • INSTAGRAM
    • TWITTER
No Result
View All Result
Bioengineer.org
No Result
View All Result
Home NEWS Science News Biology

Riddle of the sphinx

Bioengineer by Bioengineer
March 22, 2024
in Biology
Reading Time: 3 mins read
0
Sphinx tile - order 1, 2, 3
Share on FacebookShare on TwitterShare on LinkedinShare on RedditShare on Telegram

Why is the heart slightly on the left side of the body for most people? Why is DNA almost always a right-handed helix? Same with alpha helices, the building blocks of proteins. Chirality, or handedness, is everywhere in biology, but the reasons can be a mystery.

Sphinx tile - order 1, 2, 3

Credit: Huber, et. al, Physical Review Research, 2024

Why is the heart slightly on the left side of the body for most people? Why is DNA almost always a right-handed helix? Same with alpha helices, the building blocks of proteins. Chirality, or handedness, is everywhere in biology, but the reasons can be a mystery.

Greg Huber, a biophysicist and researcher at the Chan Zuckerberg Biohub San Francisco, spent three years exploring these questions and more using a simple asymmetric shape that lives on the triangular lattice, and that has received little academic attention – the sphinx tile. He and his collaborators – Craig Knecht, Walter Trump, and Robert Ziff – found unexpected properties related to its chirality. Their study, “Entropy and chirality in sphinx tilings,” was published recently in Physical Review Research.

Composed of six equilateral triangles (a hexiamond), the sphinx has an intrinsic handedness, coming in either left- or right-handed orientations. It is the only known asymmetric hexiamond that can tile every order of itself, meaning all sphinxes scaled by a factor n can be tiled by n•n smaller unit sphinxes. In other words, an order-2 sphinx can be made from 4 sphinx tiles, an order-3 sphinx can be made from 9, and so on. The numbers of tile arrangements or layouts possible, beginning from the single unit sphinx, start out small: 1, 1, 4, 16, …, but not for long.

As the number of sphinxes in a tiling goes up, the number of possible layouts increases superexponentially. For example, an order-5 sphinx has 153 possible tilings (shown below), order-6 has nearly 72,000 tilings, and order-13 a whopping 1030, or 10 to the order 30! (That’s a 1 with 30 zeros.)

The asymmetry of the tile provided rich avenues to explore chirality. Take the simple matter of placing two tiles side by side. There are 46 (or 47, depending on how you count) different ways for two sphinx tiles to form a dyad. (In contrast, there is only one way for two unit squares to form a dyad.)

And they can be tiled in such a way that they have low chiral energy, meaning most neighboring sphinxes are in the same orientation or high chiral energy. 

Huber, leader of the Theory Group at the San Francisco Biohub, emphasizes that this endeavor was more than an abstract exercise. He notes that geometry and chirality both have important but often overlooked connections to biology. Virus capsids, for example, have a geometric symmetry (the “quasi-equivalence principle”) based on the same lattice.

“The universe shouldn’t favor one handedness over another, but at scale after scale, chiral preferences emerge,” Huber says. “Chirality can be very mysterious, and the sphinx tiles’ surprising chiral interactions were the motivation for this work.”



Journal

Physical Review Research

DOI

10.1103/PhysRevResearch.6.013227

Article Title

Entropy and chirality in sphinx tilings

Article Publication Date

4-Mar-2024

Share12Tweet8Share2ShareShareShare2

Related Posts

Aureobasidium Boosts Citrus Pectin’s Antioxidant Power

Aureobasidium Boosts Citrus Pectin’s Antioxidant Power

October 28, 2025
blank

Killer Whale Genomes Reveal Long-Term Mutation Purging

October 28, 2025

AAAS Expands Science Partner Journal Program with Launch of Cancer Communications

October 28, 2025

Z-GENIE: Easy Tool for Predicting Z-DNA Regions

October 28, 2025

POPULAR NEWS

  • Sperm MicroRNAs: Crucial Mediators of Paternal Exercise Capacity Transmission

    1287 shares
    Share 514 Tweet 321
  • Stinkbug Leg Organ Hosts Symbiotic Fungi That Protect Eggs from Parasitic Wasps

    310 shares
    Share 124 Tweet 78
  • ESMO 2025: mRNA COVID Vaccines Enhance Efficacy of Cancer Immunotherapy

    198 shares
    Share 79 Tweet 50
  • New Study Suggests ALS and MS May Stem from Common Environmental Factor

    135 shares
    Share 54 Tweet 34

About

We bring you the latest biotechnology news from best research centers and universities around the world. Check our website.

Follow us

Recent News

Examining Frailty, Multimorbidity, Sleep, and Anxiety in Seniors

Mechanoluminescence Without Crystals Opens New Horizons for Next-Gen Materials

Aureobasidium Boosts Citrus Pectin’s Antioxidant Power

Subscribe to Blog via Email

Enter your email address to subscribe to this blog and receive notifications of new posts by email.

Join 67 other subscribers
  • Contact Us

Bioengineer.org © Copyright 2023 All Rights Reserved.

Welcome Back!

Login to your account below

Forgotten Password?

Retrieve your password

Please enter your username or email address to reset your password.

Log In
No Result
View All Result
  • Homepages
    • Home Page 1
    • Home Page 2
  • News
  • National
  • Business
  • Health
  • Lifestyle
  • Science

Bioengineer.org © Copyright 2023 All Rights Reserved.